Special offer. See more information about Outbyte and uninstall instructions. Please review EULA and Privacy policy.

iTechGuides is reader-supported. When you buy through links on our site, we may earn an affiliate commission. As an Amazon Associate I earn from qualifying purchases. Learn more

Benchmark single-qubit gate speed and fidelity as two related but separate measurements. Read the calibrated single-qubit gate duration for a specific native operation, then measure its operational error with single-qubit randomized benchmarking (RB). A useful result reports nanoseconds per gate, error per Clifford (EPC) or error per gate (EPG), T1 and T2 coherence, readout error, calibration state, compilation details, timestamps, and uncertainty. Without that context, a fast-looking gate or a low error number cannot be compared fairly with another qubit, calibration cycle, or processor generation.

What this benchmark actually measures

A quantum processor does not have one universal “gate speed” or “gate fidelity.” Each qubit, native instruction, pulse schedule, compiler version, and calibration can change the result. Start by choosing one operation on one qubit—for example, X, SX (square-root of X), or RX—and define exactly what is being compared.

  • Speed is the calibrated duration of the finite-duration operation, normally reported in nanoseconds per gate.
  • Operational fidelity is inferred from how reliably the processor preserves a prepared state through a sequence of gates. Standard RB usually reports an average error per Clifford; conversion can produce an error per primitive gate.
  • Coherence headroom comes from T1 and T2, which indicate how much relaxation and dephasing can occur during the gate.
  • Measurement contribution is represented by readout error and should not be mixed into the gate-error number.
  • Stability is the repeatability of those values across timestamps, recalibrations, and experimental conditions.

A virtual RZ rotation is a special case. It is implemented as a software frame update rather than a driven pulse, so a provider may report zero duration and zero reported error for it. Do not compare that software operation with a finite-duration X or SX pulse as though they were equivalent physical actions.

Special offer. See more information about Outbyte and uninstall instructions. Please review EULA and Privacy policy.

Define a fair comparison before collecting data

Fix the operation and qubit

Record the qubit identifier and the exact native instruction. “Single-qubit fidelity” is incomplete unless it says which gate was benchmarked. If the processor exposes ID, SX, X, and RX properties, keep the operation label exactly as the backend reports it. An RX gate may also require an angle; record that angle and whether the compiler decomposed it into another basis.

#1 Best Overall
Sale
Compressed Air Duster,130000RPM Super Power Cordless Air Duster,Rechargeable Brushless Blower,3 Gear Adjustable Blower with LED Light,Dust Remover for Computer/House/Outdoor/Car
  • Powerful Turbo Fan:CAGIWIRU Electric Air Duster have reached speed up to 130000RPM,Can efficient remove dust and debris.With LED light and Three Adjustable Speed to meet with different cleaning tasks.
  • With Attached USB C Fasting Charging cable.Charing 3 hours,Enjoy up to 240 minutes of use on the lowest setting, For third speed can use for 25mins.with four charging options to meet with your needs.
  • Wide Application: attached 5 different nozzles,making it suitable for a variety of scenes, such as car,pet, pc, keyboards, and other electronic devices. It also serves for office and home clean duster.
  • Handy Design & Portable:Cordless air duster electric nozzle is Light weight and small size, design and comfortable to hold and space saving, convenient to carry around. You can put it in your room or inside the car without taking up space.
  • Economical &Reusable: Built durable materials with a long-lasting battery,our CAGIWIRU air duster it's a sustainable alternative to disposable air cans.

Fix scheduling and spectator conditions

State whether the gate ran in isolation or while neighboring qubits were active. Simultaneous spectators can create crosstalk that is invisible in an isolated experiment. Also record direction where the hardware or pulse schedule makes direction meaningful, inter-gate delays, reset behavior, and whether measurement and reset were included in the timing window.

Preserve the software and calibration context

Save the backend name and revision, compiler or transpiler version, pulse or instruction definition, calibration timestamp, and experiment start and end times. IBM describes daily benchmarking that produces T1, T2, measurement-fidelity, and gate-error metrics; those values can drift with calibration timing and experimental conditions. A result without a timestamp is therefore not a durable device specification.

Comparison axis What to record Why it matters
Duration Calibrated nanoseconds for the selected finite-duration native gate Separates physical pulse time from software or scheduling overhead
Operational fidelity RB-derived EPC or EPG, with the convention and uncertainty Shows average computational performance under the chosen protocol
Coherence headroom T1 and T2, plus their measurement timestamps Indicates relaxation and dephasing exposure during the gate
Measurement contribution Readout error or measurement fidelity reported separately Prevents readout faults from being misidentified as gate faults
Stability Repeated values across calibration cycles and defined intervals Reveals drift and recalibration sensitivity
Execution context Compiler, pulse schedule, waits, spectators, and shot settings Makes results reproducible and comparable

Measure single-qubit gate duration

Use the backend’s calibrated duration for the exact instruction under test. IBM’s QPU information guide exposes gate-length and randomized-benchmarking error fields for ID, SX, X, and RX operations. Copy the duration in nanoseconds rather than inferring it from a circuit diagram: a diagram’s gate symbol does not reveal pulse width, alignment constraints, or inserted waits.

Special offer. See more information about Outbyte and uninstall instructions. Please review EULA and Privacy policy.

Report the speed number correctly

The primary speed metric is nanoseconds per gate. You may also show the reciprocal idealized rate:

idealized gates per second = 1 / (duration in seconds)

For example, a duration written as d nanoseconds corresponds to 10^9 / d idealized gates per second. This reciprocal is a pulse-rate calculation, not a claim about application throughput.

Rank #2
EVEO® Screen Cleaner Spray Kit (Streak-Free) TV Screen Cleaner for Smart TV, Lcd, LEd, Oled | Computer Screen Cleaner Spray and Wipe Microfiber Cloth - TV, Monitor, Laptop, iPad, Car - 6.7oz 1 Pack
  • Screen Cleaner is Your Screen’s New Bestfriend! - EVEO is proud to present a screen cleaner that’s perfectly suited for your TV. Meet your new screen cleaner, computer screen cleaner, laptop cleaner, iPad cleaner, Macbook,tv cleaner or any other electronic device. Our screen cleaner spray and wipe along with the included plush microfiber cloth, easily removes dust, fingerprints & other smudges on the screen’s surface. Clean effectively for a streak-free screen
  • Gentle on your Screens - Our screen cleaner spray and wipes is compatible to be used even for the most sensitive LCD, LED, CRT, and OLED screens in proper use. Be at ease knowing that this product is compatible with all the major brands: LG, SONY, Samsung, Sharp, iPad, iPhone, Android screens, Kindle, PC monitors - we’ve got you covered! Can be used as LCD screen cleaner, tv cleaner, smart tv screen cleaner, and more
  • Premium Super Soft Plush Microfiber Cloth - Included in this efficient screen cleaning kit. This screen cleaner spray and wipe has our signature plush microfiber cloth specially designed to comply with screens and monitors and leave them streak-free. Has been shown to effectively absorbs stubborn stains, zero streaks, and no fiber shedding. Always use this together with our screen cleaner for the best results
  • Easy-to-Use Screen Cleaner Kit + microfiber cleaning cloth - The EVEO Screen Cleaning Kit will easily be your new favorite tool when it comes to taking care of the things you love most, quick and easy solution for a streak-free screen. Simply screw on the sprayer gun on the screen cleaner bottle. Spray the cleaning liquid onto the microfiber cloth, then wipe the screen until desired cleanliness & shine is achieved.
  • Quality Screen Care Kit Worth Purchasing - Enjoy a convenient Screen Cleaner anytime, anywhere you need it. Your satisfaction is our top priority. We stand behind the quality of our products and that’s why, you shouldn’t be worrying at all. We manufacture the Best Screen Cleaner. and can be used for laptop cleaning kit, laptop screen cleaner, tv screen cleaner for smart tv. MacBook screen cleaner, monitor cleaner or screen cleaner spray for electronic devices with microfiber cleaning cloth

Explicitly state what the duration excludes. A pulse-duration result normally excludes queueing, readout, reset, classical processing, and any inter-gate waits. If your question is how quickly a complete workload finishes, measure circuit-layer time or wall-clock throughput separately and include those overheads. Never present pulse duration alone as end-to-end processor speed.

Special offer. See more information about Outbyte and uninstall instructions. Please review EULA and Privacy policy.

Run standard single-qubit randomized benchmarking

Randomized benchmarking estimates average operational error while reducing sensitivity to state-preparation and measurement (SPAM) errors. The standard one-qubit experiment prepares a reference state, applies random Clifford operations, appends a mathematically compensating inverse Clifford, and measures whether the reference state survived.

Choose a controlled sequence design

Select a sequence-length grid, such as several increasing values of m, and a fixed number of independent randomizations at each length. The exact grid and counts are part of the benchmark definition. Use the same lengths, randomization count, shots per sequence, inverse-generation method, and fit procedure for every qubit or device in the comparison.

  1. Prepare the reference state. Usually initialize the computational-basis state used by the backend’s standard protocol. Record reset and initialization assumptions.
  2. Generate random Clifford sequences. For each selected length m, draw many random one-qubit Clifford strings using the same sampling method across all comparisons.
  3. Append the inverse Clifford. Compute the single Clifford that ideally returns the accumulated sequence to the starting state. The inverse is part of the experiment, not an optional cleanup gate.
  4. Compile consistently. Decompose the Clifford operations into the processor’s native basis with the same compiler or transpiler settings. Save the resulting instruction stream, because the number of primitive pulses per Clifford affects EPG conversion.
  5. Execute many shots. Run enough repetitions to estimate the survival probability at every length and randomization. Keep shot count fixed when comparing conditions.
  6. Measure in the computational basis. Define survival as the probability of observing the expected reference outcome. Keep readout calibration separate from the RB fit.
  7. Average by sequence length. Average survival across randomizations at each m; retain the spread so the fit uncertainty reflects finite sampling and sequence-to-sequence variation.
  8. Fit the decay. Fit survival to an exponential-with-offset model such as A p^m + B, where p is the decay parameter and A and B absorb preparation and measurement offsets.

Inspect the fit rather than trusting one number

Plot survival probability against sequence length and show the fitted curve and uncertainty. Check for non-monotonic behavior, poor residuals, or a late-time floor that the model cannot describe. Such features can indicate leakage, drift, insufficient randomizations, or a mismatch between the assumed Markovian decay and the device behavior. Report the sequence grid, randomization count, shots, fit model, parameter uncertainty, and any data excluded with a reason.

Convert the RB decay into a labeled fidelity metric

For a one-qubit depolarizing interpretation, average gate fidelity is one minus average gate error. The important qualification is what “gate” means. Standard RB most directly produces an error per Clifford (EPC), because each sequence step is a Clifford operation. If you want the error of a primitive X, SX, or RX pulse, report an error per gate (EPG) and state the conversion convention.

Special offer. See more information about Outbyte and uninstall instructions. Please review EULA and Privacy policy.

Keep EPC and EPG distinct

A Clifford generally compiles into a variable number of primitive basis gates. Dividing EPC by an average primitive count is only an approximation unless the conversion model accounts for the basis and error assumptions. IBM documents explicit EPC/EPG conversion helpers for one-qubit basis gates; use the helper or formula appropriate to the dimension and basis, and record which convention was applied.

Rank #3
Sale
BladeHawks RGB Gaming Mouse Pad Extra Large Extended 31.5x12 Inch-Black | LED mouse pad with 14 lighting modes, covers keyboard & mouse, anti-slip rubber base, waterproof surface, USB powered
  • 【Large size】:Measuring 800 x 300 mm/ 31. 5×12 inches, which is wider and taller than others. Large mouse pad can perfectly fit your keyboard and mouse of any size, and there is also ample space for peripherals such as phones, tablets, etc.
  • 【LED backlight mouse pad】:Blade Hawks RGB mouse pad provides 7 static modes and 7 dynamic modes will give you the options you are looking for. Power-off memory function remembers the last lighting mode you selected. The super glow fiber Chroma will give you a colorful gaming setup that you want.
  • 【Anti-slip rubber base】:Made from Natural rubber, this gaming mousepad will firmly grip your desktop, allowing you to enjoy the ultimate precision in the games you are most passionate about. It also comes with a texture that enhances this ability even further.
  • 【Smooth and waterproof surface】: Micro-textured cloth surface, for extremely precise mouse control and a smooth movement. When liquid splashes on the gaming mouse pad, it forms water droplets and slides down. Will not delay your work or gameplay.
  • 【Plug and play】: This mouse and keyboard pad is powered by USB, plug and play, no driver required. One button control light modes. Press one time to change the lighting mode, press twice to change the brightness, press and hold about 3 seconds turn ON/OFF.

Do not write “fidelity 99.9%” without naming the metric. A complete label looks like “RB error per Clifford,” “converted SX error per gate,” or “average gate fidelity inferred from the one-qubit depolarizing model,” followed by uncertainty and timestamp. If the provider reports a gate-error field directly, preserve whether it is an RB-derived value, a per-Clifford value, or a per-primitive value.

Understand the historical NIST figure

A trapped-ion randomized-benchmarking demonstration hosted by the National Institute of Standards and Technology reported a one-qubit error probability of 0.00482(17) per randomized pi/2 pulse. The parenthetical notation expresses the reported uncertainty. This is a 2007 historical result, not a universal present-day target and not a direct prediction for another processor technology.

Isolate a particular gate with interleaved randomized benchmarking

Standard RB averages the implemented Clifford set. If the question is specifically “How good is this X or SX gate?”, use interleaved randomized benchmarking (IRB). Construct a reference RB experiment and a second experiment in which the target gate is inserted between the random Clifford operations. Compare the two fitted decay parameters under otherwise identical conditions.

Special offer. See more information about Outbyte and uninstall instructions. Please review EULA and Privacy policy.

IRB estimates the target operation only under assumptions about error composition, gate independence, and the relationship between reference and interleaved sequences. Report those assumptions and the uncertainty of the comparison. A large apparent difference can also arise from compilation changes, pulse collisions, leakage, or drift between the two experiments, so randomize execution order or interleave reference and target datasets when practical.

Relate gate error to T1, T2, and readout error

Use coherence as a diagnostic, not a substitute for RB

Compare the measured RB error with a coherence-limit estimate derived from the gate duration and the measured T1 and T2. A short gate leaves less time for relaxation and dephasing, but it can still have poor fidelity because of control-amplitude error, calibration mismatch, leakage, or crosstalk. Conversely, a longer pulse can be accurate if its control errors are lower. T1 and T2 therefore provide explanatory context rather than a replacement for an operational benchmark.

Keep readout error separate

Readout error affects the observed survival probability and can obscure a gate problem. Record the backend’s readout error or measurement fidelity at the same calibration state, but do not add it to the gate-error field or subtract it informally from EPC. The RB offset parameters absorb some SPAM effects; they do not turn readout into a measured gate property.

Rank #4
Sale
Vaydeer Wrist Rest for Keyboard and Mouse, Computer Ergonomic Wrist Support Pad, Soft Memory Foam Arm Cushion for Desk, Palm Hand Office Laptop Typing
  • 【Softer and More Comfortable】Vaydeer wrist rest has unique diamond pattern, which is the combination of softness and aesthetics. The materials of wrist rest are improved into higher quality memory foam and covered with silky smooth lycra. The computer wrist rest makes you as comfortable and cushiony as like rest your wrists on clouds.
  • 【Ergonomic Wrist Saver】The wrist rests for keyboard and mouse comes with a 17.32×3.15×0.83 inch keyboard wrist pad and a 5.94×3.15×0.83 inch mouse wrist support. Based on ergonomic design, the unique concave shape is the perfect fit for your wrist joints. The wrist rest pad fits most computer keyboards and laptops, improve hand and wrist posture, release your wrist and arm stress.
  • 【Non-Slip Rubber Bottom】Featuring an anti-skid silicone base on the bottom, this wrist keyboard support stays firmly in place on your desk, preventing the padding from sliding around, ensuring stable and consistent wrist support during extended computer sessions.
  • 【Better Experience & Pain Relief】Our keyboard arm rest is beneficial to alleviate the soreness caused by direct contact and friction between your arm and a hard desk surface, reducing the risk of wrist fatigue or carpal tunnel. The soft texture of memory foam can evenly distribute the pressure around your wrists and provide good support with just enough give.
  • 【Helpful in Multiple Scenarios】Whether you're working, studying, writing, typing, gaming, this keyboard and mouse rest combo is an essential accessory to add comfort and support to your hands and wrists. It’s also a great gift for men, women, family, friend, coworker, gamer, teacher, etc.

Test drift and recalibration effects

Repeat the benchmark after a defined interval, after recalibration, and after meaningful compiler or pulse changes. Preserve start and end timestamps for every run. Compare the full distribution, not only the best value: median, spread, and outliers reveal whether a gate is consistently usable or merely excellent at one calibration moment.

Special offer. See more information about Outbyte and uninstall instructions. Please review EULA and Privacy policy.

When RB is not enough: leakage, crosstalk, and predictive models

RB is an average operational metric. It can hide gate-dependent errors, coherent over-rotations, time-correlated noise, leakage outside the computational subspace, and crosstalk from simultaneous operations. A low EPC does not prove that every Clifford or every circuit layer behaves equally well.

Use gate-set tomography (GST) when you need a detailed, predictive model of the complete implemented gate set. GST can expose gate-dependent and coherent effects that an averaged RB decay compresses into one parameter. IBM Research describes GST as a detailed, predictive characterization method for processor logic operations. For multi-qubit workloads, add cycle-level or layer-level tests that activate the spectators and scheduling patterns used by the application.

Compare processors and qubits with a common reporting table

The following layout keeps unlike quantities from being conflated. Populate every row from the same experiment definition and calibration window; if a provider does not state a value, write “not stated” with the source and date rather than inferring it.

Field Qubit A Qubit B Processor or run notes
Native gate and angle Record exact instruction Record exact instruction Do not mix virtual RZ with driven pulses
Single-qubit gate duration Nanoseconds, calibrated Nanoseconds, calibrated State whether waits and scheduling are excluded
RB result EPC or EPG with uncertainty EPC or EPG with uncertainty Include fit model and sequence settings
T1 and T2 coherence Values and timestamps Values and timestamps Use as coherence context
Readout error Separate measurement metric Separate measurement metric Do not fold into gate error
Simultaneous spectators Inactive or specified activity Inactive or specified activity Controls crosstalk exposure
Calibration and software Backend revision, compiler, timestamp Backend revision, compiler, timestamp Required for reproducibility
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Support on Ko-Fi

Common failure modes and how to correct them

Calling a pulse rate “processor speed”

Symptom: A report converts nanoseconds to gates per second and presents that as application throughput.
Correction: Label it idealized pulse throughput and separately measure circuit-layer or wall-clock throughput with readout, reset, waits, queueing, and classical processing included.

Special offer. See more information about Outbyte and uninstall instructions. Please review EULA and Privacy policy.

Comparing virtual RZ with X or SX

Symptom: A zero-duration, zero-reported-error RZ appears to dominate a driven gate.
Correction: Explain that RZ is a software frame operation and compare only operations with equivalent physical meaning.

Best Value
Sale
Under Desk Cable Management Tray No Drill, Metal Mesh Cable Management Under Desk with Clamp Mount, 2 Hole Cable Tray with Wire Management and Cord Organizer for Home Office Standing Desk
  • 【No Drill Mounted】Cable management tray can be assembled in as little as 3 minutes or less-simply. Side clips easily clampe the edge of desk, pass through the holes on the sides, and secure excess cables with baskets. Desk cable management supports inward or outward installation to meet your needs in different scenarios, and provides you with great convenience when collecting and organizing wires.
  • 【Rubber Pad Protects Desk】Wire organizer under desk built-in soft rubber pads on the clamp protect your desk from scratches, so you will not damage your furniture or office.
  • 【Sturdy and Beautiful】Cord management under desk is made of high-quality carbon steel and holds about 15 lbs. The wire basket has 2 holes on each side of the tray to enable your cables to pass freely. Cable baskets are suitable for desk thickness use from 0.4" to 2.4".
  • 【Space Saving & Keep Organized】Desk cable management tray holds all your power cords, outlet strips, USB hubs and computer transformers hidden from your feet, and the data cables will not enter the vacuum cleaner to keep your desk clean and tidy. Desk wire organizer is also suitable for use in the kitchen and outdoors.
  • 【Reduce Safety Risks】Cable tray under desk keeps all plugs away from your kids, no more worry about tripping. Using 2 holes wire tray saves extra space, helps you easily cabling and wire protection. The mesh design is not easy to accumulate dust, but avoids safety accidents caused by messy wires.

Reporting EPC as though it were X-gate error

Symptom: “The X error is 0.2%” is derived directly from a Clifford RB fit.
Correction: Call the measured quantity EPC, then provide a documented EPG conversion if the basis, dimension, and assumptions support it.

Ignoring compiler changes

Symptom: Two runs use different decompositions or pulse schedules but are treated as the same experiment.
Correction: Freeze compiler settings, save the compiled instruction stream, and report the primitive-gate composition.

Using one calibration snapshot as a permanent specification

Symptom: A gate value is quoted without a date.
Correction: Include calibration and run timestamps, then repeat after recalibration or other meaningful device changes.

Free tools Windows power users keep installed

One-click scans. No signup required.

Special offer. See more information about Outbyte and uninstall instructions. Please review EULA and Privacy policy.

Over-interpreting a low average error

Symptom: A favorable EPC is used to claim absence of leakage, coherent error, or crosstalk.
Correction: Add IRB, simultaneous-operation tests, GST, or cycle-level methods that target the suspected effect.

Publication-ready reporting checklist

  • Identify the processor, backend revision, qubit ID, native gate, and any RX angle.
  • Give the calibrated single-qubit gate duration in nanoseconds and define excluded overheads.
  • State whether operation was isolated or simultaneous with spectator activity.
  • Record pulse or instruction definitions, compiler/transpiler version, and decomposition.
  • Describe state preparation, sequence-length grid, randomization count, inverse construction, and shots.
  • Show survival data, the A p^m + B fit, residuals, and parameter uncertainty.
  • Label the result as error per Clifford or error per gate; explain every conversion.
  • Report T1 and T2 coherence and readout error separately, with matching timestamps.
  • Give experiment start/end times and calibration state; repeat to quantify drift.
  • Explain whether the result is standard RB, interleaved RB, GST, or another method.
  • List limitations involving SPAM, leakage, coherent errors, time correlation, and crosstalk.

Interpreting the final result

The most defensible conclusion is multidimensional: one gate may be faster but less accurate, while another may be slower yet have greater coherence headroom or better stability. Choose according to the workload and report both axes. For processor comparisons, prefer a matched protocol over headline numbers: same sequence design, same shot and randomization budgets, equivalent compilation assumptions, equivalent spectator activity, and calibration timestamps close enough to make the conditions meaningful.

A complete benchmark therefore reads like: a specified native gate on a specified qubit took a stated number of calibrated nanoseconds; standard or interleaved RB produced a clearly labeled EPC or EPG with uncertainty; T1, T2, readout error, compiler, pulse schedule, calibration state, and timestamps explain the context; and follow-up tests establish whether the average hides leakage, crosstalk, or drift.

Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.

Special offer. See more information about Outbyte and uninstall instructions. Please review EULA and Privacy policy.