Base64 Encoder and Decoder Online - Free Tools
Turn a file or some text into a Base64 string, or take a string and get the file back. Every tool runs in your browser. Nothing is uploaded, there is no size cap, and there is no signup.
PDF Tools
- PDF to Base64
Turn a PDF into a string. Gives you the data URI, a ready iframe embed snippet, and the raw characters for an API.
- Base64 to PDF
Paste a string and get the document back. Shows a preview first, and takes both raw text and a full data URI.
Image Tools
Four options depending on the format you have and what you want back:
- PNG to Base64
For flat icons and logos. Returns an HTML img tag and a CSS background rule you can paste as they are.
- JPG to Base64
For photos. JPG and JPEG are the same format here, and no quality is lost because the file is not re-saved.
- Image to Base64
The catch-all. Takes WebP, GIF, SVG, BMP and AVIF as well, and sets the right data URI prefix for each.
- Base64 to Image
Paste a string and see the picture. Read the format off the first few characters before you download it.
- SVG to Base64
Gives you a URL-encoded data URI as well as Base64, and tells you which of the two is smaller for your file.
- Any Image Format
WebP, GIF, BMP and AVIF too. Sets the right data URI prefix and hands you the img tag and CSS rule.
Text and Debugging
- Base64 to Text
Decodes as you type and repairs messy input: data URI prefixes, line breaks, URL-safe characters and missing padding.
- Text to Base64
Type and the string appears as you type. Handles accents, emoji and any language through UTF-8.
- Base64 Validator
Tells you why a string will not decode, names the file type it holds, and repairs what it can.
- File to Base64
Takes any file at all. Zip, docx, csv, fonts, video, even extensions nobody recognises.
Audio and Other Languages
- MP3 to Base64
Encodes audio and hands back a working HTML audio tag. WAV, OGG, M4A and FLAC work the same way.
- PDF a Base64 (Espanol)
La misma herramienta en espanol, con el data URI, el codigo embed y la cadena suelta.
- PDF para Base64 (Portugues)
A mesma ferramenta em portugues, com o data URI, o codigo embed e a string pura.
What Base64 Encoding Actually Does
Base64 rewrites binary data using just 64 plain characters: A to Z, a to z, 0 to 9, plus and slash. Every 3 bytes of the original become 4 of those characters.
The point is safe travel. Email bodies, JSON fields, HTML attributes and URLs all expect text. Raw bytes get mangled in those places. Base64 survives them intact. That is why a contract has to go through PDF to Base64 before it can ride inside an API request.
Three Things People Get Wrong About Base64
- It is not encryption. There is no key and no secret. Anyone can decode a string in one step, so it must never hide a password or private data.
- It does not compress. The output is about 33% bigger than the input, never smaller. A 1 MB file gives roughly 1.37 MB of text.
- It is not a file format. A Base64 string of a PDF is not a PDF. Something has to decode it first, which is what Base64 to PDF and Base64 to image are for.
Nothing You Convert Leaves Your Browser
Most converters work by sending your file to a server, doing the job there, and sending the result back. Every tool here does the opposite. Your browser reads the file with the FileReader API and does the work on your own machine.
So there is no copy of your contract, photo or database dump sitting in an upload folder. No account, no email, no stored history. Open the tab, convert, close the tab.
It is faster too. No upload bar, no queue, no rate limit, and no file size cap, because there is no shared backend to protect.
Common Questions
Are these tools free?
Yes. No signup, no account, no paid tier, no watermark. There is nothing to pay for because there is no server doing the work.
Are my files uploaded anywhere?
No. Everything runs in your browser. Open your network tab while you convert and you will see no request go out.
Is there a file size limit?
No fixed cap. Your own device memory is the limit. Very large files can make the tab slow while it works.