Fix Base64 Encoding Errors
Decode, re-encode, and troubleshoot Base64 strings quickly and safely.
Try it now
Try it now
Open Base64 Encoder & Decoder with a ready-to-run example.
When you need this
- You received a Base64 payload and need to inspect it.
- You need to re-encode text with proper padding.
- A token looks Base64 but fails to decode.
How to do it with Daily Developer Tools
- Paste the Base64 value into the Base64 tool.
- Click Decode to see the original text.
- Use Encode to generate a clean Base64 string.
Tips / common pitfalls
- Trim whitespace and line breaks before decoding.
- Base64URL uses - and _; convert to standard Base64 if needed.
- Invalid padding often means the string was truncated.
Examples & test data
Input example
SGVsbG8sIGRldmVsb3BlcnMh
Expected output
Hello, developers!
Input example
user:password
Expected output
dXNlcjpwYXNzd29yZA==
FAQ
What is Base64URL?
Base64URL replaces + and / with - and _ for URL-safe encoding.
Why do I see invalid padding errors?
The string might be truncated or missing trailing = characters.
Is decoding done on a server?
No. Decoding runs locally in your browser. No uploads.
Can I copy the decoded output?
Yes. Use the copy buttons to grab either input or output.
Related tools
Privacy-first: runs locally in your browser. No uploads.