Validators

User Agent Validator

Validate user agent strings and check for common browser, bot, and device token formatting directly in your browser.

User Agent Validator

Validate user agent strings and check for common browser, bot, and device token formatting directly in your browser.

This tool runs in your browser. Your input is processed locally and is not uploaded.

About this Tool

Use this free User Agent Validator to check whether a user agent string looks correctly formatted. It can help detect empty values, malformed product tokens, broken comments, unusual spacing, missing version parts, and common browser or bot string issues. The validation runs directly in your browser.

Examples

Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36
Googlebot/2.1 (+http://www.google.com/bot.html)

Frequently Asked Questions

What does this user agent validator check?

It checks whether a user agent string has a plausible structure, including product tokens, versions, comments, and common formatting patterns.

FAQ

Does this identify every browser or bot?

No. User agent strings vary widely and can be spoofed. This tool checks format and common patterns, not guaranteed identity.

FAQ

Is my user agent string uploaded?

No. The validation is designed to run locally in your browser.

FAQ

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