How to use the Base64 Decoder
- Paste a standard Base64 string into the input, or import a UTF-8 text file containing it.
- The decoded text appears immediately. Whitespace around or within the encoded input is ignored.
- Copy the result or download it as a text file. Use Base64 Encode in the toolkit to perform the reverse operation.
What this tool does
Base64 represents bytes with the letters A–Z and a–z, digits 0–9, and the symbols + and /. The = character provides padding where needed. It is an encoding, not encryption: anyone with the encoded data can decode it. This page decodes UTF-8 text; it is not a binary image or file decoder.
A working example
Choose Try an example above to load this input into the converter.
Input
SGVsbG8gZnJvbSAwMUNvbnZlcnQhOutput
Hello from 01Convert!Common errors and practical limits
- Standard padded Base64 must have a character count divisible by four. Check for missing or extra = characters.
- URL-safe Base64 uses - and _ instead of + and /. Use Base64URL Decode in the toolkit for that variant.
- Valid Base64 can represent binary data rather than text. A UTF-8 error means this text decoder cannot display those bytes as valid UTF-8.
Frequently asked questions
Is Base64 safe for passwords or API keys?
No. Base64 does not protect a secret. Keep credentials private even if they are encoded, and do not save them in cloud snippets.
Why does the decoder reject my string?
Invalid characters, missing padding, extra padding, non-canonical padding bits, or invalid UTF-8 bytes can cause a rejection. This page preserves your input and shows an error instead of guessing.
Can I decode a JWT here?
Use Inspect JWT in the toolkit or the main workspace. JWT segments use Base64URL. Inspecting the decoded claims does not verify a token's signature or establish that it is trustworthy.
Is my input uploaded?
Conversions run on your device. No account is required, and input is not uploaded automatically. The optional Appwrite connection checks service availability at startup; only choosing to save a cloud snippet sends workspace content to your account.