You can make a PDF smaller while keeping it usable, but no setting guarantees a large reduction with no visible change. The safest approach is to keep the original, try moderate compression first, then check the result at the size and on the device or paper where you’ll use it. If the file still exceeds your upload limit, adjust image and document-optimization settings selectively.
Choose a compression approach for your PDF
Start by considering what is making the file large and what must remain clear. PDFs with scans or photographs contain image data that can often be reduced; text and vector artwork may gain less from image compression. Compression settings can also affect search, forms, links, and compatibility.
| PDF type or use | What to try | What to inspect |
|---|---|---|
| Mostly text, few images | Try a basic or moderate compressor first. If the document is already mostly text and vector content, aggressive image reduction may offer little benefit. Font and unnecessary-item optimization may help, but Adobe does not quantify the reduction for an individual file. | Searchable text, links, and any interactive elements you need. |
| Scanned pages | Use conservative image settings first; the page itself is raster imagery, so resolution and compression can affect readability. | Small print, stamps, handwriting, and fine detail at normal reading size. |
| Photographs or image-heavy reports | JPEG or JPEG2000 can reduce file size, but they are lossy and discard image data. | Photographs at the likely viewing size. Keep a higher-quality original for print or archival use. |
| Charts, line art, or flat-color diagrams | ZIP compression is suited to illustrations with flat-color regions, according to Adobe’s optimizer guidance. | Thin lines, labels, and crisp edges. |
| Print or production file | Use controlled settings and check the requirements with the print provider instead of choosing an online “smallest size” setting by default. | Fonts, fine detail, compatibility, and the provider’s output requirements. |
| Sensitive or confidential file | Use a workflow approved by the document owner or your organization. | Where the file is processed and the service’s terms. |
Downsampling reduces image resolution by merging original pixels into larger pixels, which can remove fine detail, as Adobe explains in its PDF Optimizer settings. The right amount depends on the particular document and its intended use; there is no universal resolution threshold that guarantees every scan will remain legible.
Compress a PDF with Acrobat on the web
- Open Adobe’s instructions for compressing PDFs online and go to Convert > Compress a PDF.
- Select or upload your PDF, then choose High, Medium, or Low compression. Start with a moderate choice rather than aiming immediately for the smallest file.
- Select Compress, then download or access the resulting file as provided by the service.
- Open the compressed copy and inspect it before sending or replacing the original.
Adobe says this web workflow optimizes files by removing embedded fonts, compressing images, and eliminating unnecessary items; it also says the compressed result is saved to Adobe cloud storage. The product page states a maximum file size of 2 GB, but that is a vendor-stated limit and may change; check Adobe’s current online compression page before relying on it. For confidential documents, assess your organization’s rules and the service’s terms before uploading. The exact retention period and deletion controls for this compression feature are not established in the cited Adobe guidance.
#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 Acrobat desktop for more control
Adobe documents advanced optimization for Acrobat Pro, Premium, or Studio on desktop. Access and labels can vary by operating system and version; confirm current plan and interface details in Adobe’s Compress & Optimize a PDF guide.
- In Acrobat, choose Save as Other > Optimized PDF.
- Choose Standard for a preset, or adjust the optimizer options for more control.
- Review image downsampling and compression first. Use image settings suited to the content: photographic images have different needs from flat-color diagrams and fine line art.
- Check font, transparency, object, user-data, and cleanup options. These can remove or alter items such as embedded fonts, thumbnails, search indexes, comments, forms, multimedia, or private data. Do not discard content or metadata you still need.
- Set the compatibility target deliberately. Adobe notes that choosing an older Acrobat version can limit available compression features.
- Save the optimized PDF as a new copy, then verify it before using it in place of the original.
Adobe’s advanced size-reduction guide describes the desktop controls and the optimizer settings reference explains image and other options. In general, lossless compression preserves the underlying image data, while lossy compression removes data to reduce size. Adobe’s archived Acrobat 8 help says, “JPEG is lossy, which means that it removes image data and may reduce image quality; however, it attempts to reduce file size with the minimum loss of information.” That archived explanation describes the general distinction, not current Acrobat interface behavior.
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.
Check quality and document function before sharing
Compare the compressed copy with the original at the intended viewing size. A page that looks acceptable when zoomed out may have blurred small text or broken fine lines when read closely; a print-bound file should be assessed for print use, not only on a screen.
- Read small text and inspect fine rules, diagram labels, stamps, and handwriting.
- Check photographs for visible artifacts or loss of detail.
- Search for text if the PDF needs to remain searchable.
- Test links, forms, and other interactive content that recipients rely on.
- Confirm the PDF opens in the software and version your recipient is likely to use.
If quality or functionality is unacceptable, return to the untouched original and use less aggressive image settings or retain more of the document data. Make another copy rather than repeatedly optimizing an already compressed PDF.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
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
Rank #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.
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.
