Compress PDF — free, private, in your browser
Compress PDF shrinks a PDF by rendering each page with PDF.js and re-encoding it as a JPEG image, then rebuilding the PDF with pdf-lib - either at a quality level you pick, or stepping down until it fits a target size you set. Free, no signup, 5 runs a day. It runs in your browser; nothing you add is uploaded.
📦 Compress PDF
Shrink file size by re-rendering each page at lower image quality. Runs in your browser.
Re-renders each page at the chosen scale and JPEG quality. Best for image-heavy PDFs; text-only PDFs may not shrink much.
About Compress PDF
Reduce the size of a PDF so it's easy to email or upload, without sending it to anyone first. TaimurTools redraws each page as a compressed image right inside your browser, so the compression happens on your device and your file is never uploaded to a server. That works best on scans and image-heavy files; the text in the result is part of the image, so it can no longer be selected or searched. No signup, no watermark.
- Shrink PDF file size in-browser
- Adjustable image quality
- No upload — fully private
- Free, no signup or watermark
Step-by-step guide: How to compress a PDF for free without uploading
Runs on your device
Your file is opened and processed by JavaScript inside this page. It is never uploaded and we never receive it. The page does download the processing library it needs from a public CDN the first time you use it - that request carries no part of your file.
Free tier: 5 runs per day for this tool, counted in your browser. The counter resets at midnight UTC and is not shared between browsers or devices.
How TaimurTools handles data · Why most of these tools run on your device
What this tool is for
- Getting a scan under an upload size limit
- Emailing a heavy image-led brochure
- Archiving scans where exact text fidelity does not matter
| What it does | Shrinks a PDF by rendering each page with PDF.js and re-encoding it as a JPEG image, then rebuilding the PDF with pdf-lib - either at a quality level you pick, or stepping down until it fits a target size you set. |
|---|---|
| Accepted input | One PDF (application/pdf). |
| What you get back | A PDF of the same page count in which every page is now a JPEG image. |
| Limits | Capped at 5 runs per day for this tool, counted in your browser and reset at midnight UTC. Long documents also take time, because every page is rendered and re-encoded. |
| Browser requirements | Any current desktop or mobile browser with JavaScript enabled. |
A worked example
- Input
- A 10-page scanned PDF made of photographed pages, level Balanced.
- What comes back
- A 10-page PDF that is substantially smaller, because each page is now a re-encoded JPEG.
- Worth knowing
- This is the important trade-off: the output is images. Text in the result is no longer selectable or searchable, and a text-based PDF can even get LARGER than the original. Use it on scans and image-heavy files, not on text documents.
If it does not work
The output is bigger than the original
The tool checks this for you: if compressing would make the file bigger - usual for text or vector PDFs - it says so and keeps your original instead of offering a larger file. Compression helps scans and image-heavy PDFs.
Text is no longer selectable in the result
Expected - every page became an image. Run OCR PDF afterwards if you need a searchable text layer back.
Small text looks soft or smeared
Choose Light, or leave the file uncompressed. Strong is aimed at photos, not fine print.
It takes a long time or the tab stalls
Every page is rendered at full size. Split the PDF first and compress in parts.
Nothing happens when you run it
You may have used your 5 free runs of this tool for today. The page shows a "Daily limit reached" notice; the counter resets at midnight UTC.
How to use Compress PDF
- Add your PDFDrop the PDF onto the upload area, or click to pick it.
- Pick a level or a target sizeStrong, Balanced or Light - or A target size, then type the KB limit (or tap 100 KB, 200 KB, 500 KB or 1 MB).
- Compress and downloadClick Compress. With a target, the result line shows the final size in bytes and says plainly if the target could not be reached.
When to use Compress PDF
Getting a scan under an upload limit
Job portals, e-filing sites, visa forms and HR systems often reject a file above a fixed size. A scanned contract or ID pack is the usual culprit because every page is a full-size photograph. Switch to target-size mode, type the limit, and the tool steps the quality down until the file fits.
Emailing an image-heavy brochure or catalogue
A PDF exported from a design tool with large embedded photos can be far too big to attach. Re-encoding the pages as compressed images brings it down to something an inbox will accept.
Sending a pack of photographed pages
If the PDF was built from phone photos (receipts, delivery notes, signed forms), the pages are already images, so shrinking them costs you very little that you could see.
Archiving scans where the text layer does not matter
Old paper records that were scanned and never OCR'd gain nothing from being stored at full resolution. A smaller copy is easier to keep and to share.
Working on a device you do not own
Because the compression runs in the browser tab, you can shrink a sensitive file on a borrowed or shared computer without creating an account or uploading it first.
The settings, explained
Compress PDF works by drawing each page onto a canvas with PDF.js, saving that picture as a JPEG, and rebuilding a new PDF from the pictures with pdf-lib. The three levels are three different pairs of numbers taken straight from the code:
- Strong
- Each page is drawn at 1x its nominal size (about 72 pixels per inch) and saved at 55% JPEG quality. This gives the smallest file and is meant for photos and scans you only need to read on a screen. Fine print can look soft.
- Balanced
- Pages are drawn at 1.4x (about 100 pixels per inch) at 72% quality. This is the sensible starting point for most scans: usually still readable, and noticeably smaller than the original.
- Light
- Pages are drawn at 2x (about 144 pixels per inch) at 88% quality. Use it when the document has small print or stamps and you would rather keep the file larger than lose legibility.
- A target size
- Type a limit in KB, or tap 100 KB, 200 KB, 500 KB or 1 MB. The tool redraws the pages at lower resolution and quality, step by step, and keeps the first version that fits. If none fits, you get the smallest result with a plain note saying the target was not reached. In this tool 1 KB is 1,000 bytes, which is the stricter of the two conventions portals use, so a file that passes here passes either.
What it cannot do
- The output is made of images. Text in the result is no longer selectable or searchable, links and form fields are gone, and any digital signature on the original no longer validates because the file has been rebuilt. If you need text back, run the result through OCR PDF.
- A PDF that is mostly real text can come out larger than it went in, because a page of crisp text compresses far better as text than as a picture. Do not use this tool on a text document that is already small.
- Every page is rendered at full size before it is re-encoded, so a long document is slow and a very long one can stall a phone. Split it first and compress the parts.
- Password-protected files cannot be opened. The free allowance is 5 runs per day for this tool, counted in your browser and reset at midnight UTC.
How it compares with the alternatives
Desktop programs such as Adobe Acrobat's file-size reducer, or command-line tools such as Ghostscript, can downsample the images inside a PDF while leaving the text as text. For a report, a contract typed in Word or anything that has to stay searchable, that is the better route and gives smaller, cleaner results than this tool can.
Many online compressors upload your file to a server, which is quick and often keeps the text, but means a copy of your document leaves your device. Compress PDF is the opposite trade-off: nothing is sent anywhere, at the price of turning pages into pictures. Pick it when the file is a scan, when it is sensitive, or when you cannot install software.
How in-browser processing works, and exactly which tools are the exception, is explained on the why client-side page.
Getting a better result
Start at Balanced
Open the result and zoom to 100% on the smallest text before you send it. Only go to Strong if you have to, and only go to Light if Balanced looks soft.
Split long files first
Compress the cover letter and the 40-page scan separately, then merge them again. You keep the text pages crisp and only shrink the heavy ones.
Keep your original
The result is a lossy copy. Never overwrite the file you started with.
Remember the 1,000-byte KB
If a portal says 100 KB and shows a result at 99.5 KB here, it will pass; the tool counts the smaller figure on purpose.
More questions about Compress PDF
Which level should I try first?
Balanced. If the result is still over your limit, switch to a target size and let the tool step down for you. Light is for documents with small print.
Will signatures and stamps still be visible?
Yes, as part of the page picture. They are no longer separate objects, and a cryptographic signature no longer verifies, so do not compress a document that has to stay signed.
Can I compress several PDFs at once?
No, one PDF per run. Each run counts against the 5 free runs per day for this tool.
Why does the result say the target could not be reached?
Some documents will not compress that far without becoming unreadable. You get the smallest version the tool could make. Try splitting the file, or remove pages you do not need to send.
Related tools
- Split PDF - break a long file into parts before compressing
- Merge PDF - join the parts back together afterwards
- OCR PDF - put a searchable text layer back on the compressed scan
- Image Compressor - shrink the photos before they go into a PDF
Step-by-step walkthrough: read the full guide.
We build fillable PDF forms, contracts, invoices and document templates that customers and staff can complete in any PDF viewer, with calculations, validation and your branding. The free tool above stays free.
Frequently asked questions
Is my PDF uploaded to a server?
No. Rendering and re-encoding both happen in this page, using PDF.js and pdf-lib downloaded from a CDN. The file itself never leaves your device.
Why did my file get bigger?
Because the tool converts pages to JPEG images. A PDF that was already mostly text compresses badly as images. This tool is for scans and photo-heavy PDFs. If that happens the tool tells you and offers no download, so you keep the original.
Will the text still be searchable?
No. The output pages are images. Run OCR PDF on the result to add an invisible text layer back.
Is there a daily limit?
Yes - 5 runs per day for this tool, counted in your browser and reset at midnight UTC. TaimurTools Pro lifts the cap.
Can I compress a PDF to an exact size, like 100 KB?
Yes. Choose "A target size" and type the limit in KB. The tool redraws the pages at lower resolution and quality, step by step, and keeps the first version that fits. If none fits, you get the smallest one and a note saying so. KB is counted as 1,000 bytes, so the file passes portals that count either way.