Is there really no limit on how many files I can process?

No artificial limit. There is no counter, no cooldown and no cap that appears after a certain number of runs. The only real limits are the per-file size cap and your device's memory.

Will it get slower if I use it a lot?

No. Each run is independent and nothing accumulates between them. If a later run feels slower, it is usually browser memory pressure — reload the page and it will be back to normal.

What is the largest file I can use?

150 MB per file. These limits are about what a browser tab can hold comfortably, not about tiering.

How small can you make my PDF?

It depends entirely on what is in it. Scanned documents and image-heavy files often drop by 70 to 90 per cent. A text-only PDF exported from a word processor is already efficient and may barely change — the tool will tell you when that is the case rather than shipping a pointless file.

Will the text still be selectable after compression?

With the Lossless level, yes — nothing about the page content changes. With Balanced, Strong or Target size, pages are re-rendered as images, so text becomes part of the picture and is no longer selectable or searchable. Choose Lossless if searchable text matters more than size.

What does the target size mode actually do?

It tries a sequence of six settings, each combining a lower render resolution with a lower image quality. As soon as one produces a file at or under your target it stops and hands that back. If none of them reach the target, you get the smallest usable version along with a note saying the target was not met.

Why did my file get no smaller?

Some PDFs are already optimised — text-only documents from Word or LaTeX typically are. In that case re-rendering would make the file larger, not smaller, so the tool keeps the better of the two results and tells you it could not improve on it.

Are the page dimensions preserved?

Yes. Even when a page is re-rendered at a lower resolution, the output page keeps the original point size, so the document still prints at the correct physical dimensions.

Unlimited Compress PDF

Shrink a PDF so it fits an upload limit or an email attachment.

Drop your PDF file here

or browse your device

A single PDF file, up to 150 MB. Files are processed on this device.

There is no counter on this page. Run the compress pdf tool once, or run it thirty times this afternoon, and the thirtieth run behaves exactly like the first — same speed, same options, same output.

Daily caps exist on other sites for a straightforward reason: their processing happens on servers that cost money per file, so usage has to be metered. This tool runs on your own device, which means the marginal cost of your next file is zero and there is nothing to meter.

The same logic removes the queue. You are not waiting behind other people's jobs on shared infrastructure, because the work is happening locally. What limits throughput is your own processor, not somebody else's capacity planning.

Almost every PDF that is too large is too large for the same reason: it contains page images at a far higher resolution than anyone will ever look at. A phone photo of a receipt dropped into a document can easily be 8 MB on its own. PDFNova's compressor attacks that directly, and it tells you honestly what it achieved.

There are four levels. Lossless rewrites the file structure without touching a single page, which helps some documents and does nothing for others. Balanced and Strong re-render pages at a lower resolution and quality. Target size keeps trying progressively harder settings until the file fits the number you gave it, which is what you want when a portal refuses anything over 1 MB.

How to compress a PDF file

Add your PDF
Drop in the file you need to shrink. Files up to 150 MB are accepted.
Pick a compression level
Start with Balanced. Choose Lossless if the document must not be re-rendered at all, or Target size if you have a hard limit to meet.
Set your target, if you have one
With Target size selected, enter the ceiling in kilobytes. 1024 KB is about 1 MB, 500 KB is a common email-friendly limit.
Compress
Progress is reported page by page. Larger documents take longer because every page is re-rendered.
Check the numbers and download
The results panel shows the original size, the new size and the saving. Preview the document before downloading to confirm it is still readable.

Why use this compress pdf tool

No daily cap

There is no per-day, per-hour or per-session file limit. Nothing changes on your tenth or fiftieth run.

No queue

Work runs on your own device rather than shared servers, so there is nobody ahead of you and no waiting room.

No throttling

The tool does not slow down after repeated use, and there is no faster paid version of it being held back.

A real size target

Give the tool a number in kilobytes and it will keep trying harder settings until the output fits, rather than compressing once and leaving you to guess.

It never makes things worse

If aggressive compression produces a larger file than a simple structural rewrite, the smaller of the two is what you get. The result is never bigger than what a plain re-save would give you.

Honest reporting

You are shown the before and after size and the percentage saved. If a document was already well optimised and could not be improved, the tool says so instead of pretending.

Features

Four levelsLossless, Balanced, Strong, and an iterative Target size mode.
Size targetingSix progressively stronger passes are tried until your target is met.
Before and afterEvery run reports the original size, final size and percentage saved.
Preview firstRead the compressed document in the browser before you commit to it.
Cancel mid-runStop a long compression at any point without leaving a partial file behind.

When people use this

Meeting an upload limit

Government portals, job applications and court filing systems routinely cap uploads at 1, 2 or 5 MB. Target size mode exists for exactly this.

Emailing a scanned document

A scanned twenty-page contract can easily exceed 25 MB. Balanced compression usually brings it under a typical mail attachment limit while keeping it perfectly readable.

Publishing to a website

Smaller PDFs load faster for readers on mobile connections and cost you less bandwidth.

Archiving a folder of documents

Compressing before archiving keeps years of paperwork from filling a drive, at a quality level that is still fine to read.

What actually limits how much you can process

There is no artificial cap, but there are real, physical limits worth knowing. Individual files are capped at 150 MB. These reflect what a browser tab can comfortably hold in memory rather than a commercial decision.

The practical ceiling is your device's available memory. A phone with several other tabs open will struggle with a very large document where a laptop would not notice it. If a large job fails, closing other tabs and trying again usually resolves it.

For very large batches, working in groups is more reliable than pushing a single run to its limit. Nothing is lost by doing so — the result of processing in batches is identical to processing everything at once.

How compression works

The Lossless level loads the document with pdf-lib and re-saves it using cross-reference object streams. This packs the file's internal structure more tightly without altering any page content — useful for documents with a lot of structural bloat, neutral for everything else.

The other levels take a different route. Each page is rendered to a canvas with pdf.js at a chosen scale, encoded as a JPEG at a chosen quality, and embedded into a fresh PDF at the original page dimensions. Target size mode walks through six scale-and-quality pairs from 1.5x at 82 per cent quality down to 0.55x at 34 per cent, stopping at the first one that meets your number. Whatever route is taken, the final output is compared against the plain lossless rewrite and the smaller of the two wins.

Privacy

Your files are not uploaded. When you add a PDF file, your browser reads it from your device into the memory of the tab you are looking at, and the compress pdf operation runs there using your own processor. Nothing is transmitted to any server at any point.

That means there is no file for anyone to store, no retention policy to trust, and no deletion schedule to take on faith. The document exists only in the memory of an open browser tab, and it is released the moment you close it, reload the page, or press start over.

The site uses standard anonymous analytics to count page views and how often each tool is used. Those events record which tool ran and whether it succeeded — never a file name, never file contents, and never anything that could identify a document or the person processing it.

No account is required, so no personal information is collected. There is no profile, no history and nothing tied to an identity, because no identity was ever created.

Security

The strongest security property this tool has is structural: your file never travels anywhere, so there is no transmission to intercept and no server-side copy to breach. This is not a policy that could change — it is a consequence of where the code runs.

You can verify it in about thirty seconds. Open your browser's developer tools with F12, select the Network tab, and use the tool. You will see the page's scripts load — including the PDF libraries, which are fetched on demand the first time a tool runs — and then nothing further. No request carrying your document is ever made.

For a stronger test, disconnect from the network once the page has loaded. The tool will keep working exactly as before, which is only possible because nothing is being sent.

Uploaded files are validated in the browser before anything runs: the extension must match what the tool accepts, the file must not be empty, and it must be within the size limit. Malformed documents produce a clear error and a retry option rather than a silent failure.

What this tool does not do

Being clear about limits is more useful than a feature list that quietly omits them. Any level other than Lossless converts page text into an image, which removes text selection, copy and paste, and searchability. Compression also cannot reduce a file below the size its content fundamentally requires.

If you need capabilities beyond that — redaction, PDF/A conformance, OCR, or scripted batch processing across thousands of documents — dedicated desktop software genuinely earns its licence fee, and this is not trying to replace it. For the specific job of producing a compressed PDF, everything you need is on this page.

Frequently asked questions

Is there really no limit on how many files I can process?: No artificial limit. There is no counter, no cooldown and no cap that appears after a certain number of runs. The only real limits are the per-file size cap and your device's memory.
Will it get slower if I use it a lot?: No. Each run is independent and nothing accumulates between them. If a later run feels slower, it is usually browser memory pressure — reload the page and it will be back to normal.
What is the largest file I can use?: 150 MB per file. These limits are about what a browser tab can hold comfortably, not about tiering.
How small can you make my PDF?: It depends entirely on what is in it. Scanned documents and image-heavy files often drop by 70 to 90 per cent. A text-only PDF exported from a word processor is already efficient and may barely change — the tool will tell you when that is the case rather than shipping a pointless file.
Will the text still be selectable after compression?: With the Lossless level, yes — nothing about the page content changes. With Balanced, Strong or Target size, pages are re-rendered as images, so text becomes part of the picture and is no longer selectable or searchable. Choose Lossless if searchable text matters more than size.
What does the target size mode actually do?: It tries a sequence of six settings, each combining a lower render resolution with a lower image quality. As soon as one produces a file at or under your target it stops and hands that back. If none of them reach the target, you get the smallest usable version along with a note saying the target was not met.
Why did my file get no smaller?: Some PDFs are already optimised — text-only documents from Word or LaTeX typically are. In that case re-rendering would make the file larger, not smaller, so the tool keeps the better of the two results and tells you it could not improve on it.
Are the page dimensions preserved?: Yes. Even when a page is re-rendered at a lower resolution, the output page keeps the original point size, so the document still prints at the correct physical dimensions.

Browse every PDF tool, or read the help and FAQ pages. Details of how files are handled are in the privacy policy.