Base64 Decode
Decode Base64 strings back to readable text in your browser — free, instant and private. Unicode-safe; nothing ever leaves your device.
Output
100% in your browser — nothing you type is ever uploaded.
How to Base64 decode text
- Paste your Base64 string into the input box above.
- The decoded plain text appears instantly in the output box.
- Click Copy to copy the decoded text to your clipboard.
What this tool does
This tool reverses Base64 encoding back to plain text. It reads the Base64 alphabet (A–Z, a–z, 0–9, +, /, =), rebuilds the original byte sequence, then decodes those bytes as UTF-8 — so text that was encoded with accented letters, CJK characters or emoji comes back unchanged.
Common reasons to Base64 decode text
- Reading the payload of a JSON Web Token or Basic Auth header while debugging an API.
- Inspecting a
data:URI to see the original inline content. - Recovering the source text from a config value, log line or email header stored in Base64.
- Verifying that an encoder in your own code is producing the expected output.
Related tools
- Base64 Encode — convert plain text into Base64.
- JWT Decoder — decode a full JSON Web Token's header and payload at once.
Frequently asked questions
- Is my Base64 string uploaded anywhere?
- No. The decoding happens locally in your browser. Nothing is sent to a server, so tokens, credentials or private notes stay on your device.
- Does this handle Unicode and emoji correctly?
- Yes, as long as the string was Base64-encoded from UTF-8 bytes (which is how most tools, including this one, encode text). The decoded output is read back through a UTF-8 decoder, so accented letters, CJK text and emoji come back intact.
- What happens if I paste invalid Base64?
- The tool shows a clear error message instead of garbage output. Common causes are missing padding characters, stray whitespace, or characters outside the Base64 alphabet (A–Z, a–z, 0–9, +, /, =).
- Why does the decoded text look garbled?
- If the original data was not UTF-8 text — for example a compressed file, an image, or binary encrypted with another algorithm — decoding it as text will not produce readable output, even though the Base64 itself is valid.
- Is decoding the same as decrypting?
- No. Base64 is not encryption, so decoding requires no password or key — anyone can reverse it instantly. If the original text needs to stay secret, Base64 alone provides no protection.
- Can I decode a JWT with this tool?
- You can decode a single JWT segment here, but a full JSON Web Token has three dot-separated Base64url segments and its own padding rules — use the dedicated JWT Decoder for that instead.