Base64 Validator - Validate Base64 Encoded Strings Online
Validate Base64 encoded strings instantly with detailed format checking and content type detection. Free online Base64 validator with comprehensive error reporting.
How to Use Base64 Validator - Step by Step Guide
Enter Base64 String
Start by pasting your Base64 string into the input area for validation.
Automatic Validation
The tool automatically validates your Base64 string format, checking for valid characters, proper padding, and structure integrity.
View Results
Get detailed validation results including format status, content type detection, and size information.
What is Base64 Validation?
Base64 validation is the process of verifying that a string adheres to the RFC 4648 Base64 encoding standard. A valid Base64 string must contain only the 64 defined characters (A-Z, a-z, 0-9, +, /) and proper padding (=) characters.
Validation checks for common errors like invalid characters, incorrect padding, improper length, and malformed data. This is essential for data URLs, JWT tokens, and MIME email encoding to ensure data integrity during transmission.
Why Validate Base64 Strings?
Validating Base64 strings before processing prevents runtime errors, data corruption, and security vulnerabilities. Invalid Base64 can cause decoding failures in browsers and applications, leading to application crashes or data loss.
For REST APIs, validating Base64 input helps maintain secure coding practices and ensures data quality before storage or transmission.
Frequently Asked Questions
How do I validate a Base64 string?
Simply paste your Base64 string into the validator. It automatically checks format, padding, character validity, and provides detailed error messages if invalid.
What makes a Base64 string valid?
A valid Base64 string contains only A-Z, a-z, 0-9, +, / characters with proper = padding at the end. The length must be a multiple of 4 (including padding).
Is this Base64 validator secure?
Yes, completely secure. All validation happens entirely in your browser using client-side JavaScript. Your data never leaves your device.
Can this detect the content type?
Yes! The validator attempts to detect whether the decoded content is an image, text, JSON, or other data type by analyzing the binary signature and structure.
Is this validator free?
Yes, completely free with no size limits, no registration required, and unlimited validations with full privacy protection.
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