TextEncoder produces UTF-8 bytes before Base64 encoding. Decoding uses TextDecoder with strict UTF-8 validation.
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Data & developer
Base64 Encoder & Decoder
Encodes UTF-8 text as Base64 or decodes valid Base64 to text. Base64 is an encoding format, not encryption.
✓ Free✓ No account✓ In-browser
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What does this tool do?
Encode Unicode text to Base64 or decode it back.
ResultReady
Your result will appear here.
APPLICATION AND DECISION GUIDE
Base64 Encoder & Decoder: method and usage
Encodes UTF-8 text as Base64 or decodes valid Base64 to text. Base64 is an encoding format, not encryption.
Enter Unicode text to encode, or Base64 representing UTF-8 text to decode. Confirm the shape first with a small example containing no personal data.
Depending on direction, the output is Base64 or decoded Unicode text, with source and output byte measurements.
Practical steps
- Enter text.
- Choose encode or decode.
- Review sensitive output before sharing it.
Encode and decode Çay ☕; both Ç and ☕ must survive unchanged. Decoding /w== must fail UTF-8 validation.
Base64 is not encryption. This tool handles UTF-8 text, not arbitrary binary files or image reconstruction.
Suitable use cases
- Preparing data payloads
- Quick sample conversion
- Diagnosing encoding issues
Base64: a Unicode round-trip check
Encode the exact text Çay ☕. The result represents its UTF-8 bytes in Base64; retain the final padding character. Switch to decode and paste the output back: the Ç and coffee symbol must both survive. Character count is not byte count. This sample catches encoding mistakes that an ASCII-only test would miss, without using any personal information.
Çay ☕w4dheSDimJU=Input that should fail
/w==/w== represents valid Base64 bytes, but its decoded byte 0xFF is not valid standalone UTF-8 text. This text decoder should reject it; it is not an image or arbitrary-file decoder. Base64 provides no secrecy or encryption. An encoded password, access token, or personal record is still exposed to anyone who can decode it.
LEARN THE WORKFLOW
Guides for this tool
Safe In-Browser Handoffs Between JSON, CSV, and Base64
Build reusable flows that reduce copy-paste while preserving data-type, encoding, and error boundaries.
Read guide →A Systematic Workflow for Debugging JSON, JWTs, and APIs
Trace malformed bodies, encoding mistakes, expiry, and JWT claims in a safe, repeatable order.
Read guide →ABOUT THIS TOOL
Frequently asked questions
What input does Base64 Encoder & Decoder accept?+
Enter Unicode text to encode, or Base64 representing UTF-8 text to decode. Enter text.
What does Base64 Encoder & Decoder return?+
Depending on direction, the output is Base64 or decoded Unicode text, with source and output byte measurements. TextEncoder produces UTF-8 bytes before Base64 encoding. Decoding uses TextDecoder with strict UTF-8 validation.
How should I validate Base64 Encoder & Decoder output?+
Encode and decode Çay ☕; both Ç and ☕ must survive unchanged. Decoding /w== must fail UTF-8 validation.
Does Base64 Encoder & Decoder send or store input on a server?+
Tool input is processed in the active tab. Saving to the Workstation or transferring to another tool is a separate choice. Consider browser extensions and shared devices separately; the privacy page explains advertising and network connections.