---
title: "Browser fingerprint check — free"
description: "What any site sees when you open it: IP, WebRTC, time zone, Canvas, WebGL and fonts. No sign-up, nothing is stored."
url: https://umbreta.com/en/fingerprint-check/
lang: en
---

# Browser fingerprint check

What any site sees when you open it. The check runs in your browser; we store nothing and ask no one to sign in.

![Umbi studies a mask embroidered with a fingerprint pattern through a magnifier](https://umbreta.com/_astro/u-fp.B_eL7vzC_Zh6L8p.webp)

## What a site sees right now

This is what the page read from your browser in a couple of seconds. Open it in a profile with a proxy to see what a platform sees.

### Your browser

Checking in your browser… Without JavaScript there are no values, but what each line means and how to fix it is below. #### Network

IP address —

The address you came from. A site tells your country, city and provider from it and checks everything else against it.

**How to fix:** Work through a proxy in the country you are supposed to be in, and keep one IP per account.

WebRTC —

The browser can tell a site your network's addresses past the proxy. We look for addresses it gives away without asking any outside server.

**How to fix:** Turn WebRTC off or replace the addresses with the proxy's. An address like 192.168… shows the site your home network. #### Environment

Time zone —

The zone the browser tells sites. Platforms check it against the IP's country: Kyiv behind a German proxy is a clear mismatch.

**How to fix:** Set the proxy country's zone. If the zone's name and the clock offset disagree, it was only half replaced, and the site sees that.

Language —

The languages in the browser's settings and the language it writes dates in. If they differ, the swap shows.

**How to fix:** Pick the proxy country's languages, or keep yours, but the same everywhere: in the language list and the interface language.

Screen —

Screen size and pixel density. A rare pair helps pick you out among thousands of visitors.

**How to fix:** Use common sizes: 1920 × 1080, 1536 × 864, 1440 × 900. The window must not be bigger than the screen. #### Fingerprint

Canvas —

The browser draws an invisible picture; graphics card and fonts make it come out slightly different for each person. Sites keep its hash as a tag.

**How to fix:** The hash should be stable and different for every profile. If it changes on every read, the site sees noise, and that is a tag too.

WebGL —

The graphics card the browser names to sites. Software rendering gives away a virtual machine or automation.

**How to fix:** The card must fit the system: Apple on a Mac, Intel, AMD or NVIDIA on a Windows laptop. WebGL turned off entirely stands out too.

Fonts —

Which system fonts are installed. The set gives away the system, and rare fonts a particular person.

**How to fix:** Fonts must fit the profile's system: Windows fonts in a macOS profile are a mismatch.

## What a browser fingerprint is

A set of parameters — graphics card, fonts, screen, language — by which a site recognises you without cookies. Two matching fingerprints, and the site decides it is one person.

## Why check before work

A proxy changes only the IP. If the language, time zone and WebRTC are still your computer’s, the platform sees the mismatch and links the accounts.

## What we do with the data

Nothing. The check runs in your browser. One request goes to the server, to learn which IP sites see; we do not record it. The report is not stored.