Data & APIs
Base64 encoder & decoder
Free Base64 encode/decode with UTF-8 support. Copy results locally—no uploads.
Overview
Use standard Base64 when you need transport-safe text, quick data URI experiments, or debugging auth headers. Encoding uses TextEncoder so emoji and non-Latin scripts round-trip correctly. Decoding strips whitespace from the pasted blob before `atob`, which matches how many APIs emit wrapped lines.
UTF-8 safe: non-ASCII characters are encoded correctly using the browser TextEncoder. Switch direction anytime—the output updates as you type.
Frequently asked questions
Is this the same as MIME Base64 or PEM Base64 with line breaks?
It is the common Base64 alphabet without line breaks. If you need PEM-style 64-column wrapping, wrap the output manually.
Why does Base64 decode fail or show an error?
The string must be valid Base64 (alphabet, padding). Corrupted padding or non-ASCII characters inside the encoding will throw an error.
Does Base64 encode/decode upload my text or leave my browser?
No. Encode and decode run entirely with local JavaScript APIs.
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