Base64 to UTF-8 Decoder

How to Use Base64 to UTF-8 Decoder

1. Paste your Base64 string into the input. Line breaks are fine - we strip whitespace before decoding by default.
2. Leave URL-safe on if you’re pasting a JWT fragment or anything from a URL - - and _ become + and / before decoding, and the stats line flags URL-safe.
3. Watch the stats line. You’ll see N bytes decoded vs M codepoints rendered. If codepoints < bytes, you’ve got multi-byte UTF-8 sequences (emoji, CJK, etc). The non-ASCII count shows how many codepoints are outside the 0-127 range.
4. Check for replacement chars. If the stats say 3 ✱ replacement, three byte sequences weren’t valid UTF-8 and became U+FFFD (�). That usually means the source was actually binary (image, ZIP), not text - the Base64-to-hex tool might serve you better.
5. BOM handling. If your Base64 was made from an Excel-saved text file, there’s likely a UTF-8 BOM prefix. We detect and strip it by default; the stats show BOM stripped so you know.
6. Copy or download. Copy writes to clipboard; Download saves decoded-<timestamp>.txt with UTF-8 encoding. Keyboard shortcut: Ctrl+Enter / Cmd+Enter decodes and copies in one step.
7. Fix errors. If you see “Invalid Base64: unexpected character”, the error names the exact offending char and its position - remove it or switch tools if it’s supposed to be there.