Turn a Base64 string back into readable text or a downloadable file, even with a data URI prefix or line breaks in it. Decoding runs in your browser with no upload.
Your files are processed in your browser, on your own device. Nothing is uploaded to a server.
Base64 Decode turns a Base64 string into the text or file it came from. Paste the string as you found it, with a data URI prefix, line breaks or the URL-safe alphabet, and the tool sorts it out. Text appears on screen, and binary results download as a file. It is free and runs in your browser with no upload.
Real Base64 rarely arrives clean. It comes wrapped in lines inside an email source, carrying a data URI prefix from a web page, or written with the URL-safe alphabet from a token. Paste it as it is. The tool strips a data URI prefix when it finds one, ignores spaces and line breaks, and reads both alphabets before it decodes a single byte.
Decoded text shows only when the bytes really are text. The tool checks whether the result reads as valid UTF-8, and when it does, you see the text itself. When it does not, the bytes belong to a file, and you get a download named binary.bin. If you made the string yourself earlier, the Base64 Encode page is the other half of the pair.
API responses are the common case. A service hands back a JSON payload with an attachment, a signed document or an image carried as one long string, and the string is useless until it is decoded. Paste it here and the file or the text is in your hands a moment later.
Email and storage hide strings too. Message sources carry attachments in Base64, databases and config files hold encoded values, and logs fill up with strings nobody on the team can read at a glance. Decoding turns all of that back into something a person can open and judge.
Embedded pictures are the third regular job. An image sitting inside CSS, HTML or a data URI is one paste away from being a file again. Real Base64 arrives messy, and a decoder earns its place by coping with the mess, so the line breaks and prefixes in your paste are expected here, not treated as mistakes.
Base64 carries bytes and nothing else. It does not store the original filename or the file type, so a binary result arrives as binary.bin and renaming it is part of the job. The name is lost in the encoding, and no decoder can honestly promise to bring it back.
Invalid input gets a plain error. If the string holds characters that cannot belong to Base64, or it was cut off halfway when copied, the tool stops and tells you instead of handing over garbage dressed as a result. Check for a missing chunk at the end of the string first, since a truncated paste is the usual cause.
Decoding is not checking. The tool does not inspect what a decoded file is, scan it, or clean it, and it cannot tell you whether the contents are safe. Treat any decoded file the way you would treat a download from a source you do not know, and open it with the same care.
The decoding runs on your device. Strings you paste are not sent to a server, not stored by ToolPeko and not read by anyone here. There is no account and no daily cap. Close the tab and the string and its decoded result go with it.
The decoded bytes were not readable text, so they came back as a file. Base64 does not store the original filename, so the download uses a plain name and you rename it to what it should be.
Yes. A prefix that marks the content as Base64 data is spotted and stripped before decoding, so you can paste the whole thing exactly as you copied it.
Yes. Whitespace and line breaks inside the string are ignored, which is how Base64 usually travels through email and documents anyway.
Yes. Both the standard alphabet and the URL-safe alphabet are read, so token and URL strings decode without you editing them first.
The input held characters that cannot be Base64, or the string was cut short when copied. The tool shows a plain error rather than guessing at the missing part.
No. Decoding happens in your browser, and nothing is sent to or kept on a ToolPeko server.
Same rules as this one: free, in your browser, with nothing uploaded.
Paste messy JSON, get it neat and valid.
Check JSON and find the exact line that breaks it.
Squeeze JSON down to one tight line.
Open JSON as a tree you can fold and explore.
JSON rows turned into a CSV a spreadsheet can open.
A CSV file turned into clean JSON objects.
JSON rewritten as YAML for config files.
YAML config turned into JSON you can use in code.