Privacy · 5 min read

Why most OCR tools are a privacy risk — and how to avoid it

Before you upload a photo of your tax form, receipt, or ID card to an online OCR tool, read this.

What happens when you upload to a typical OCR site

The workflow of nearly every popular online OCR tool looks like this:

  1. You upload your image.
  2. The image travels over the internet to the tool's server.
  3. The server runs OCR software on it.
  4. The extracted text is sent back to your browser.
  5. Your image — and possibly the extracted text — may be stored on their server, sometimes for days or permanently.

Most privacy policies for these tools contain language like "we may retain uploaded content for service improvement." For a photo of a birthday cake, that's fine. For a photo of your passport, tax return, bank statement, or private message — it's a serious risk.

The privacy-safe alternative: browser-based OCR

WebAssembly (WASM) has changed what's possible in a browser. It allows complex software that previously required a server — compilers, video editors, image processors — to run entirely inside your browser tab. Tesseract.js is a full OCR engine compiled to WebAssembly.

When you use imagetotextocr-phi.vercel.app, this is what actually happens:

  1. You select an image from your device.
  2. The file is read by JavaScript running in your browser tab (not sent anywhere).
  3. Tesseract.js — already loaded in your browser — processes the image locally.
  4. The text is displayed in your browser.
  5. No image data ever leaves your device.

How to verify this yourself

You don't have to take our word for it. Open the tool, then open your browser's Developer Tools (right-click → Inspect → Network tab). Select an image and click Extract Text. Watch the Network tab — you'll see the Tesseract language file load (that's normal, it's the OCR model), but you will see zero requests that upload your image data.

Try it — your documents stay on your device

Open the private OCR tool →

When does this matter most?

The open source transparency guarantee

This tool is fully open source. The source code is available on GitHub for anyone to audit. The privacy guarantee isn't a claim in a terms of service — it's verifiable in the code itself. There are no upload calls. Period.