Tools › Base64 Encode & Decode
Base64 Encode & Decode
Encode text to Base64 or decode Base64 back to text online. Handles UTF-8, emoji and accents, supports URL-safe Base64 and runs entirely in your browser.
Use it from code
The same function is available as an API endpoint. Free tier: 100 calls per day without a key. Pro lifts the limit.
curl -X POST https://spincrus.uz/api/v1/tools/base64 \
-H "content-type: application/json" \
-H "x-api-key: YOUR_KEY" \
-d '{"text":"Hello, мир! 👋","mode":"encode","urlSafe":false}'FAQ
Does Base64 encrypt my data?
No. Base64 is an encoding, not encryption: anyone can decode it. Never use it to hide passwords or secrets.
What is URL-safe Base64?
It replaces "+" with "-" and "/" with "_" and drops the "=" padding so the string can be used in URLs, filenames and JWTs. The decoder accepts both variants automatically.
Why does decoding fail with "not valid UTF-8"?
The Base64 string is valid but represents binary data such as an image or archive, not text. This tool decodes text only.
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