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Base64 Encoder/Decoder
Base64 Encoder/Decoder converts text to Base64 and back, handling full UTF-8 input rather than only plain ASCII, so accented letters, emoji and non-Latin scripts survive the round trip.
How to use Base64 Encoder/Decoder
- Paste the text or the Base64 string into the editor.
- Click Encode to produce Base64, or Decode to return it to readable text.
- Copy the result with the copy button.
Where Base64 Encoder/Decoder is useful
- Building a data URI for a small asset.
- Inspecting a Base64 API payload you received.
- Embedding a string in a place that only accepts ASCII characters.
- Decoding a token you found while debugging.
Formats, algorithms and limits
Encoding runs the browser's UTF-8-aware conversion before the standard Base64 alphabet is applied, which is what keeps emoji and non-English characters intact — a plain btoa call on such text would fail with an error. Padding characters (=) are produced as the specification requires and are accepted on the way back.
Troubleshooting and honest limits
- Base64 makes data longer — roughly a third larger — because three bytes become four characters.
- Base64 is an encoding, not encryption: never use it to protect a secret.
- If decoding fails, check that the string is not truncated; every four characters must be present.
Frequently asked questions
Is Base64 the same as encryption?
No. Anyone can decode it back to the original text instantly. Use a real encryption tool when confidentiality is needed.
Does it handle emoji and non-English text?
Yes. The conversion is UTF-8 aware, so any character your editor can hold survives the round trip.
Why is the encoded output longer than the input?
Base64 stores three bytes of data in four text characters so the result stays safe for text-only channels; that expansion is expected.
Can I decode a file's Base64 contents?
Paste the string and decode it. Very large strings load slowly in the editor, so decode in parts for huge payloads.
Related tools
Page written and reviewed by the FreeConvertio engineering team on 2026-10-14. Base64 Encoder/Decoder runs entirely in your browser — no uploads, no account and no daily limits.