Base64 Encoder / Decoder
Encode text, files and images to Base64 or decode them back — including data URIs for embedding. Everything happens in your browser, so nothing is uploaded.
Guides for this tool
Frequently Asked Questions
What is Base64 encoding used for?
Base64 converts binary or text data into a plain ASCII string using 64 safe characters. It is widely used to embed images in HTML/CSS, send data in JSON or XML, and transmit content through systems that only handle text.
How do I decode a Base64 string?
Paste the Base64 string into the decoder and the original text appears instantly. If decoding fails, the input is usually not valid Base64 or is missing padding characters.
What is URL-safe Base64?
Standard Base64 uses + and / characters, which have special meaning in URLs. URL-safe Base64 replaces them with - and _ so the encoded value can be used in links and query strings without further escaping.
Is Base64 a form of encryption?
No. Base64 is encoding, not encryption — anyone can decode it. It hides nothing and provides no security, so never use it to protect passwords or sensitive data.
Can I convert an image or file to Base64?
Yes. Switch to File mode and choose or drag in any file — an image, PDF, or anything else. You get both the raw Base64 and a ready-to-paste data URI, and images show a preview so you can confirm you encoded the right file.
What is a data URI and how do I use it?
A data URI embeds the file directly in your markup instead of linking to a separate file, for example src="data:image/png;base64,…" on an img tag or url(…) in CSS. It saves an HTTP request, which suits small icons and inline images, though large files bloat your HTML or stylesheet.
Can I turn a Base64 string back into a file?
Yes. Paste either a raw Base64 string or a full data URI and use the download button. The file type is taken from the data URI when present, and otherwise detected from the content itself, so you get a correctly named and typed file.
Are my files uploaded to a server?
No. Encoding and decoding run entirely in your browser using the File and Blob APIs, so your files never leave your device. That also means the tool keeps working offline once the page has loaded.