Mimimetr

How do you find out who leaked your PDF?

Give each person their own copy of the file with an invisible mark. Found it in someone else’s channel? Upload it to Mimimetr and the mark shows whose copy it is. Free, in your browser.

Add the mark

Everything runs in your browser. Your files and buyer list are never uploaded anywhere.

Which files does the mark work for?

Any PDF: books, courses, checklists, planners, sheet music, study materials, templates, manuals and charts. Leaks aren’t only about sewing patterns; anything that fits in one file gets passed around. JPG, PNG and WEBP images work too.

How do I add the mark?

Upload the file, type the person’s name or nickname and download their personal copy. The Buyer field works just as well for a course student or a private group member. Each person needs a separate copy. By default a visible line with the name sits at the bottom of each page, and you can turn it off.

How do I see whose copy got out?

Open the “Check a copy” tab and upload the file you found, a screenshot or a photo of the page. The name is stored in the file itself, so a PDF can be checked on any device. Screenshots and photos give only the copy ID, and your buyer list supplies the name.

What does the mark survive?

The mark survives re-printing to PDF, 100–150 dpi scans, screenshots, half-resolution copies, and rotated or blurred photos of the page. A cropped piece of bare cells without margins cannot be read.

What doesn’t the mark do?

The mark shows whose copy got out, but it doesn’t stop anyone forwarding the file. Black-and-white “document scanner” filters erase the hidden pattern, and it’s weak on very dark pages. Text retyped by hand carries no mark. We promise no legal force: the platform decides on any complaint.

The tool

Upload a PDF or image (JPG, PNG, WEBP) and enter the buyer's name or handle to create their copy with a hidden mark. You can also add a visible line.

Quick start
  1. Select a PDF or image, or drop it into the “Mark” tab.
  2. Enter the buyer's name or handle and, if needed, the order number.
  3. Click “Create personal copy” — the download starts automatically.
  4. Send exactly this file to the buyer.
or drop it here
Advanced
Hidden marks The name isn't visible on the page, but it is stored inside the file. Someone with the right tools could extract it. If the file looks like a cross-stitch chart, the marks on chart and legend pages go only into the margins: no microtext, and the invisible text and footer stay outside the grid and legend rows. That way apps like Pattern Keeper read the chart just as without the mark. The pattern layer and metadata work as usual.

Upload the PDF or image you found, or a screenshot or photo of a page. The tool checks each marking layer.

Upload the whole page or at least with its margins: a cut-out of bare cells cannot be read. If you only have a fragment, ask for the full file or find the full page.

or drop it here

Copyright infringement notice template. This is not legal advice — review the text before sending.

This template follows the structure of Art. 16(2) of EU Regulation 2022/2065 (DSA) and common DMCA requirements. It is not a legal assessment of your case. Check the form links — platforms change them. Only submit accurate information: false notices can have consequences.

Back up your buyer list

This list is stored only in this browser. Save a backup once a week and keep it somewhere safe — email it to yourself or save it to your cloud drive.

The “ID → buyer” list is stored only in this browser.

How it works

  1. 1 Create a copy for a specific buyer

    Click “Choose a file” and select your PDF or image. On a computer, you can also drag the file into this box. In the “Buyer” field, enter the buyer's name or handle. Then click “Create personal copy”. Mimimetr adds an invisible mark, and the file starts downloading automatically. If a save window opens, choose a folder and click “Save”. Done — this buyer's copy is ready, complete with an invisible signature.

  2. 2 Send the buyer the downloaded file

    This file already contains the buyer's personal mark. Send it via Telegram, Instagram or email. Just don't mix it up with the unmarked original. The buyer's details are saved under “My buyers”. For the next buyer, select the original again and create a new copy with their name. Each buyer gets their own — like a named mug in the office kitchen.

  3. 3 Found your work in someone else's channel? Check the copy

    Save the file you found, or take a screenshot or photo of the page. Open Mimimetr in the browser you used to create the copies. A PDF can also be checked in another browser if it still contains the buyer's details. Go to the “Check a copy” tab, choose the file and click “Check”. If the mark is readable, you'll see who you sold that copy to. Photos should be sharp and free of glare — Mimi the squirrel has sharp eyes, but she isn't a magician. To ask for the post to be removed, use the “Complaint” tab to prepare the text.

New: a chart from a photo

A free tool for stitchers: a photo becomes a cross-stitch chart with DMC threads, a symbol grid, a legend and a print-ready PDF. In your browser, no uploads.

Make a chart

Found a shared copy. What next?

Articles

All articles →

Questions about the mark

Is the mark free?

Yes. There’s no sign-up, and the file is processed in your browser.

Can you see the mark in the file?

At the medium level the hidden mark looks like a barely visible warm paper tint. Check the copy before you send it. The visible line at the bottom of the page can be turned off.

Where do my files go?

Nowhere. The file and your buyer list stay in your browser, and nothing is sent to a server. Back up the list, because clearing the browser deletes it.

Will the mark stop the file being forwarded?

No. The file forwards like any other. The mark only lets you find out whose copy it is.

What happens to a digitally signed PDF?

Adding the mark invalidates the file’s digital signature, so it’s best not to mark PDFs signed that way.

What should I do once I find a copy?

Talk to the person, or prepare a complaint in the Complaint tab. It’s a template, not legal advice.

About the project

Mimimetr is for people who sell their own digital files — illustrations, prints, craft patterns, planners and more — on Telegram, Instagram or their own website. We don't see your files or buyer list. The tool is free.

Mimi is an embroidering squirrel, the Mimimetr mascot. The tools are built by a team; Mimi is only there to remind you that crafts are a joy. She does not pretend to be human and never writes on her own: in the Telegram channel our team writes on her behalf.

Privacy

Full privacy page →