Free tools Windows power users keep installed
One-click scans. No signup required.
The best alternative depends on what you need to test: use DNSViz to investigate live DNS and DNSSEC behavior from a command line, and use BIND’s named-checkzone to validate a local zone file before loading it. Neither is established as a feature-for-feature replacement for Zonemaster-CLI’s broader delegation checks.
Choose by the DNS problem you need to solve
| Task | Best fit | What it covers—and what it does not |
|---|---|---|
| Trace live DNS and DNSSEC behavior from a command line | DNSViz | Its tools can probe authoritative servers and produce textual analyses or graphs. This is not evidence that it runs every Zonemaster test. |
| Inspect DNSSEC authentication paths visually | DNSViz | Its visualizations emphasize the authentication chain and resolution path; they do not establish complete parity with Zonemaster. |
| Test a zone before delegation | DNSViz CLI | It supports pre-deployment scenarios using a local zone file and alternate delegation details. Setup may involve local dependencies, including BIND’s named. |
| Check a local BIND zone file before loading | named-checkzone |
It checks syntax and integrity according to BIND’s zone-loading checks. It does not show the end-to-end parent-child delegation picture. |
| Run broad delegation-oriented checks, including parent and child data | Zonemaster-CLI | Its documented test plan covers multiple delegation and operational areas. Keep it as the reference point if that breadth is what you need. |
What Zonemaster-CLI tests
Zonemaster describes its purpose as testing DNS delegation quality. Its v2024.1 test plan covers delegation, consistency, DNSSEC, addresses, nameservers, connectivity, zone properties, and syntax. That breadth matters when choosing an alternative: a tool that validates a file or visualizes DNSSEC can be useful without answering all the same questions. See the Zonemaster documentation for the test plan and CLI options.
Zonemaster-CLI can be run as zonemaster-cli example.com or through the project’s Docker image. It supports JSON output, reporting-level configuration, selected test cases, custom root hints, and tests for undelegated zones using supplied NS and DS records. If your host environment lacks IPv6 support, its documentation advises using --no-ipv6; interpret IPv6-related output in light of the test environment rather than treating it automatically as an authoritative DNS failure. These are useful capabilities to compare against before switching.
DNSViz: the closer command-line option for DNS and DNSSEC diagnosis
DNSViz is the stronger fit when the question is how DNS resolution or DNSSEC authentication is behaving. Its tool suite includes probe to collect data, grok to analyze it, and graph and print to present results visually or as text; query supports DNS queries. Probe output can be saved as JSON for later analysis, and the tools can query authoritative servers directly or use explicitly supplied authoritative server addresses. The project documentation describes the commands and workflows at DNSViz.
Recommended Free Tools
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
Use it before delegation when you can provide the data
DNSViz’s CLI documentation describes pre-deployment testing with a local zone file and alternate delegation details for a zone that has not yet been delegated. This is not the same as a one-click web check: the setup can require dependencies and may invoke a local BIND named process. Consult the project’s README and documentation for package and configuration details; availability varies by operating-system distribution and release.
Know the current public-service limitation
The DNSViz public service notice says it is in maintenance mode. It can run new analyses, but cannot load historical analyses and will not save new ones to its database. Do not rely on the website for historical reports or persistent saved results; the CLI offers a separate workflow for saving probe data locally.
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
named-checkzone: validate a file, not a delegation
BIND’s named-checkzone checks a zone file’s syntax and integrity using the checks BIND performs when loading a zone. It is useful before loading a file into BIND, but it does not test the parent zone’s delegation, whether published nameservers are reachable, or the full DNSSEC path. Treat it as a focused local validator that complements a live DNS analysis tool—not as a general delegation-testing suite. The BIND manual page documents its behavior; the cited online manual identifies itself as development documentation (9.21.27-dev), so check the manual for the BIND version you operate.
Only run named-checkzone on zone text you trust. BIND warns that $INCLUDE directives can make its parser read files accessible to the user running the command. That is a relevant security consideration when validating files received from someone else.
Do these 3 things before closing this tab:
1Scan for outdated or missing drivers - takes under a minute2Repair Windows errors before they cause bigger problems3Fix the driver behind crashes, sound loss and screen glitchesRank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
How to choose without losing checks you rely on
- Map your current workflow. List whether you need live delegation checks, DNSSEC diagnosis, local-file validation, pre-delegation testing, machine-readable output, or selected test cases.
- Match each need to a tool. DNSViz addresses DNS/DNSSEC analysis;
named-checkzoneaddresses BIND file validation. If you rely on Zonemaster’s broader delegation suite, the cited documentation does not establish that either alternative covers it all. - Keep tools complementary where appropriate. A local file check and a live delegation analysis answer different questions; using both can be more appropriate than expecting one to replace the other.
- Check your environment before interpreting output. Confirm IPv6 availability for Zonemaster runs, and review DNSViz package requirements for your operating system and release.
The official documentation describes features and scope, not head-to-head performance. There is no basis here for claiming that DNSViz or named-checkzone is faster, more accurate, or detects more errors than Zonemaster-CLI.
Quick Recap
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
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.
