Base64 Validator
Check whether a string is valid Base64 and preview the decoded bytes. Runs in your browser.
Runs in your browser — your file never leaves your deviceFrequently asked questions
Is Base64 Validator free to use?
Yes — Base64 Validator is completely free with no limits, no watermarks and no sign-up. It runs in your browser, so there is nothing to pay for.
Are my files uploaded or stored anywhere?
No. This tool does all its work locally in your browser using your own device's power. Your files never leave your device and we never see them.
Do I need to install anything or create an account?
No installation and no account needed. Base64 Validator works on any modern browser — Windows, Mac, Linux, Android and iPhone.
How do I use Base64 Validator?
Open the tool, add your file (or paste your content), adjust any options, then press “Validate”. Your result is ready to download in seconds.