What is Base64 Validator?
Base64 Validator checks whether a string is a valid Base64 encoded payload adhering to RFC 4648 standards.
How to use Base64 Validator
Paste a Base64 string to verify validity and view decoded byte length.
Key features
- Validates RFC 4648 Base64 compliance
- 100% client-side operation
Common use cases
- Verifying API Base64 string payloads
Technical details & standards
Checks Base64 character alphabet and '=' padding compliance client-side.
Frequently asked questions
What causes Base64 validation failure?
Invalid non-alphabet characters or incorrect '=' padding length.
Is my data safe?
All processing happens entirely in your browser. Your data never leaves your device and is never sent to or stored on a server.
Does it work offline?
Yes. Once the page has loaded, most tools keep working without an internet connection.