# Timezone and IP consistency checker

> Check whether your browser timezone and language match your IP location — the exact mismatch consistency detectors read on every visit.

Source: https://mosaicbrowser.com/tools/timezone-ip-checker

## Timezone and IP consistency checker

Half of what a consistency scanner reads is whether your IP’s location agrees with your browser clock and language. This checks exactly that: your timezone, offset, locale and Accept-Language against the country and timezone of your IP, and says in plain words whether a site would see one place or two.

Your browser values are read here; your IP’s location comes from your own request to our server.

**Why four lines.** One mismatch can be innocent — people travel, expats keep a home language. Several at once is the pattern a scanner reads as a mask. The Accept-Language versus navigator.languages line is the strictest: no normal browser disagrees with itself there.

## The signal, line by line

A site can read your timezone and languages from JavaScript, your Accept-Language from the request header, and your location from your IP. When those sources disagree, the disagreement itself is the fingerprint — more telling than any single value.

### Timezone vs IP timezone

Your browser’s `Intl` timezone against the timezone your IP’s location implies. The headline check.

### Offset vs IP offset

The UTC offset now, which catches “same offset, different zone” — a weaker but still readable mismatch.

### Language vs IP country

Your primary language against your IP’s country. Advisory: travel and expats make this a soft signal, not proof.

### Accept-Language vs navigator.languages

The header your browser sent against the list JavaScript reports. These must agree; a difference is a spoofing artefact.

## Make the clock follow the exit

A VPN or proxy that changes your IP but leaves your operating-system clock and language alone is the classic half-match. Set the browser’s timezone, locale and language to the place your IP presents — and keep them together as you change exits. Doing that by hand across many profiles is error-prone, which is why Mosaic sets all three from the measured exit automatically.

1. **Open the checker.** The page reads your browser timezone, UTC offset and languages, and asks our server for the timezone and country of your IP.
2. **Compare the four lines.** It compares timezone against IP timezone, offset against IP offset, language against IP country, and your Accept-Language header against navigator.languages.
3. **Read the consequence.** Each line is a fact and a plain consequence — whether a site comparing the two would see one place or two.

### What is an IP timezone mismatch?

When your browser’s timezone does not match the timezone of your IP address’s location. A site that reads both — the clock from JavaScript, the location from your IP — sees them disagree, which is one of the first things a consistency scanner checks.

### Is a language that differs from my IP country a problem?

Not on its own — people travel and expats exist, so we show it as advisory. A clearer signal is when your Accept-Language header disagrees with navigator.languages, which no normal browser does and a spoof sometimes causes.

### How does Mosaic avoid this?

It measures each profile’s exit and sets the timezone, language and geolocation to match it. With no proxy, a profile matches the computer’s own location and falls back to the machine’s own timezone, never a table.

## Every account its own browser. One price for all of them.

Free holds 3 profiles and 10 profile creations, with no card. Pro is $49 a month for any number, or $490 a year with 2 months free. Try it for 14 days; cancel before day 14 and you pay nothing.

Mosaic is a desktop app

Email yourself the link and open it on your computer.