Base64 Decoder
Decode Base64 back to readable text, or download decoded images, PDFs and other files.
Accepts standard and URL-safe Base64, with or without padding, line breaks or a data: prefix.
Runs in your browser — your data never leaves your device.
About the Base64 Decoder
Paste a Base64 string to see what it contains. Text is decoded with full UTF-8 support. If the data is a file — such as a PNG, JPG, PDF or ZIP — the decoder recognises it and lets you download it.
It is forgiving: URL-safe Base64, missing = padding, spaces, line breaks and data:...;base64, prefixes are all handled automatically.
How to use the Base64 Decoder
- Paste your Base64 string. The decoded result appears instantly.
- If it is text, Copy it. If it is a file, click Download to save it with the right extension.
- If the input is invalid, a message explains why.
How it works
Each Base64 character represents 6 bits. Groups of four characters are turned back into three bytes. The bytes are then checked: known file signatures (for example 89 50 4E 47 for PNG or 25 50 44 46 for PDF) are recognised as files; otherwise the bytes are read as UTF-8 text.
Examples
SGVsbG8gV29ybGQh→Hello World!V0UgVG9vbHM(no padding) →WE Tools
Frequently asked questions
Why do I see "not valid Base64"?
The text contains characters that are not part of the Base64 alphabet, or it has been cut off. Make sure you copied the whole string.
Can I decode a Base64 image?
Yes. Paste the Base64 (with or without the data: prefix) and click Download — the image is saved with the correct file type.