pdfpix

Compress PDF to 4 MB

or drop one here
Compression level
Target size
Choose a PDF file first.

4 MB is 4,194,304 bytes. It holds 290 text pages, 110 pages with pictures, 130 scanned pages, 220 phone photos of pages or 150 pages scanned in colour. A stack of phone photos shrinks far below it, and a long scan fits whole. Type 4 with the unit set to MB and press Compress.

How to compress a PDF to 4 MB

  1. Choose the PDF

    Press Choose a PDF, or drop the file on the page. The file is read in this tab and is not sent anywhere.

  2. The target is already set

    This page opens at 4 MB, so there is nothing to type. Pick a different level, or enter your own smaller number in KB, if you want another size.

  3. Press Compress

    Four methods race: copy the pages into a fresh file, re-encode the placed images, cut each embedded font down to the glyphs the pages draw, and, only when no other method reached the target, redraw the pages as images with the text kept on top.

  4. Read the check, then download

    Every candidate is opened again and its characters are counted against the source. The page shows the size, the method that won and the characters kept before it offers the download.

The four methods are described in full, with the measurements behind them, in how it works.

What fits in 4 MB

From 1 MB up, the run adds a second public set of 24 files from 2.0 MB to 38.4 MB: scanned FDA approval files from 1997, NASA technical reports, and long US government publications. Every file in both sets is a public document, and the worked example on each page links to its source.

DocumentPages at the default settingPages at the smallest setting
Text documentsPages at the default setting290Pages at the smallest setting290
Text with picturesPages at the default setting100Pages at the smallest setting110
Scanned pagesPages at the default setting130Pages at the smallest setting130
Phone photosPages at the default setting55Pages at the smallest setting220
Colour scansPages at the default setting40Pages at the smallest setting150

A 3 page phone photo scan from a public CC BY dataset went from 7.5 MB to 215 KB by re-encoding the placed pictures at 150 dpi. On the public files above 4 MB, the default methods cut the median file by 76.5%.

Bytes and mail

This tool aims under 4,194,304 bytes. A form that counts in millions stops at 4,000,000. A file set to 3,900 KB, 3,993,600 bytes, clears both. A 4 MB mail limit takes a PDF of about 3 MB.

Before you send a 4 MB file

Read the result. If a picture method won, open the pages at normal zoom and check the parts that matter: signatures, stamps and small print. If the structural rebuild or font subsetting won, no pixel changed.

3 MB and 5 MB are the nearest targets.

Questions

Is there a free pdf compressor to 4mb with no upload?
This one. The file is compressed in this tab and saved to your downloads. It is never sent to a server, and there is no account.
What does a pdf compressor 4mb target do to scanned pages?
It redraws them only if the methods that change no pixel are not enough. The default redraw stops at 150 dpi and JPEG quality 60, and keeps a black and white page as a 1-bit image at 150 dpi, so the print stays sharp.
Why does my 4 MB form want 4,000,000 bytes?
It counts a megabyte as a million bytes. This tool counts 1,048,576. Set the target to 3,900 KB and the file fits both readings.
Can I check the output before I download it?
Yes. The result shows the size, the method that won and the share of characters kept. The tool verifies each candidate before it offers the file.

Related tools

Each runs in a browser tab like this one, reads its own output back before the download, and needs no account. The footer links every tool.

Where to go next