Base64 Encoder / Decoder
Encode text and files to Base64 or decode Base64 strings. Runs entirely in your browser.
About the Base64 encoder and decoder
The TConverter Base64 Encoder / Decoder converts text and files to Base64 and turns Base64 strings back into readable text. Base64 represents binary data using only letters, digits and a few symbols, which makes it safe to place inside JSON, XML, HTML, CSS, email bodies or HTTP headers that are designed for plain text. Developers run into it constantly, whether in API payloads, Basic authentication headers, configuration secrets or embedded images.
Text is encoded as UTF-8 before conversion, so characters outside the basic Latin alphabet, such as accented letters, Turkish characters or emoji, are handled correctly instead of causing errors. Decoding works the same way in reverse: the Base64 input is turned back into bytes and read as UTF-8 text. If the string is not valid Base64, you see a clear error message instead of garbled output.
You can also drag and drop any file onto the upload area, or click it to choose one. The file is read in your browser and the result is shown as a complete data URI, for example data:image/png;base64,..., which you can paste straight into an img tag or a CSS background. At the same time, the plain Base64 part without the prefix appears in the text field, so you have both forms at hand. When the file is an image, a small preview is displayed to confirm you picked the right one.
A few points are worth knowing. Base64 is an encoding, not encryption: anyone can decode it, so it should never be used to hide passwords or sensitive data. Encoded output is roughly one third larger than the original, which matters when embedding large images. The decoder expects the standard Base64 alphabet; the URL-safe variant that uses - and _ is not accepted. Decoded output is shown as text, so this page is best suited for decoding text content rather than rebuilding binary files.
Encoding and decoding run entirely in your browser. Neither your text nor your files are sent to a server. The tool is free, and no account is needed.
Frequently asked questions
Is the Base64 encoder free?
Yes. TConverter's Base64 tool is free and does not require sign-up.
Are my text and files uploaded?
No. Encoding and decoding happen locally in your browser, and nothing is sent to a server.
Is Base64 a form of encryption?
No. Base64 only changes how data is represented, and anyone can decode it. Do not use it to protect passwords or confidential information.
How do I get a data URI for an image?
In Encode mode, drop the image onto the upload area. The result is shown as a full data URI such as data:image/png;base64,..., ready to use in HTML or CSS.
Does it support Turkish characters and emoji?
Yes. Text is encoded and decoded as UTF-8, so special characters and emoji are preserved.
Why do I get an Invalid Base64 string error?
The input contains characters outside the standard Base64 alphabet or has been truncated. URL-safe Base64 that uses - and _ instead of + and / is also not accepted.