About Base64 to Text Decoder
This Base64 to text decoder turns a Base64 string back into the original text, read as UTF-8. It accepts the standard and URL-safe alphabets, and padding is optional. It is free, needs no sign-up and runs in your browser, so nothing you enter is uploaded.
Choose Decode and paste the string. Spaces and line breaks are ignored, so you can paste Base64 that was wrapped across lines in an email or a PEM block. A leading data: prefix is removed for you. The string SGVsbG8gV29ybGQ= decodes to Hello World, and so does SGVsbG8gV29ybGQ without the equals sign.
Two errors are worth knowing. Input is not valid Base64 means the text has characters outside the alphabet, or a length that cannot be right, often because a character was lost when copying. Valid Base64, but the bytes are not UTF-8 text means the decoding worked, but the data is binary, such as an image or a ZIP file. In that case, use the image preview or Download as file.
Decoding does not make anything secret again, and it does not check where the data came from. Treat decoded content from an unknown source as untrusted.
How to use Base64 to Text Decoder
- Choose Encode to turn data into Base64, or Decode to turn Base64 back into the original.
- To encode, type or paste text, or choose File or image and pick a file from your device.
- Set the options you need: URL-safe (- and _) for tokens and URLs, Keep = padding to include or drop the trailing equals signs, and Data URL to add the data: prefix with the right media type.
- To decode, paste Base64 or a full data URL. Padding is optional and spaces or line breaks are ignored.
- Read the result in the Output box. For an image, check the Image preview. For other data, use Download as file to save the decoded bytes.
- Use Copy to put the result on your clipboard.
Features
- Encodes and decodes text as UTF-8, so every language and emoji works.
- Encodes any file or image from your device. It is read in your browser and never uploaded.
- URL-safe option that uses - and _ in place of + and /, as used by JWT and URL parameters.
- Padding switch: keep the trailing = signs or drop them.
- Data URL option that writes data:text/plain;charset=utf-8;base64, or data: with the file media type in front of the result.
- Decoder that accepts both alphabets, missing padding, whitespace and a data: prefix.
- Image preview when the decoded bytes are a PNG, JPEG, GIF, WebP or BMP picture.
- Download of the decoded bytes as a file, for PDFs, images and other binary data.
- Clear errors: Input is not valid Base64, or Valid Base64 but the bytes are not UTF-8 text.
Worked examples
SGVsbG8gV29ybGQ= gives Hello World
4pyTIMOgIGxhIG1vZGU= gives ✓ à la mode
Multi-byte characters are rebuilt from UTF-8.
SGVsbG8* gives Input is not valid Base64.
The asterisk is not part of the Base64 alphabet.
Privacy: how it works
- Your text, files and images are processed by code in your browser tab. Nothing is sent to Ulkaa or to any other server, which you can confirm in the Network tab of your browser developer tools.
- That matters for Base64 in particular, because people often paste API keys, tokens and private images into these tools. Because there is no upload, there is nothing to leak, but remember that anything you paste into any web page is visible on your screen.
Tips
- If a decoded result looks like random symbols, the original was probably binary, such as an image or a PDF. Use Download as file instead.
- A string that starts with eyJ is very likely Base64 for a JSON object that begins with {". JWT parts do.
- Pasting a JWT part? The segments are URL-safe Base64 without padding. Decode each of the dot-separated parts on its own.
- To embed a small image in CSS or HTML, choose File or image, tick Data URL, and paste the result into src or url().
Frequently asked questions
Is it really free?
Yes. There is no price, no trial and no credit card. Ulkaa Tool does the work with your own device, so there is no server bill to pass on to you.
Do I need an account?
No. There is no sign-up and no login. Open the page and use it. An Ulkaa account is not needed for anything on this tool.
Does it run in my browser?
Yes. Your text and files are processed by code running in your browser tab, on your own device.
Is my data uploaded?
No. Your text and files are never sent to Ulkaa or to anyone else. You can check this yourself by watching the Network tab in your browser developer tools while you use the tool.
How do I decode Base64 to text?
Choose Decode and paste the Base64 string. The tool turns it back into text immediately. If it is not valid you see an error rather than wrong output.
Why do I get strange characters or an error after decoding?
The data may be binary, not text, or it may be text in an encoding other than UTF-8. The tool reads UTF-8 only and shows a message when the bytes are not valid UTF-8.
Does it decode URL-safe Base64?
Yes. Strings that use - and _ instead of + and / decode as they are, and missing = padding is added back automatically.
More Base64 Encoder and Decoder pages
- Base64 Encoder and DecoderEncode text, files or images to Base64, or decode a Base64 string or data URL back to text, an image or a file.
- Text to Base64 EncoderType or paste text and get its Base64 encoding straight away.
- Image to Base64 ConverterPick an image and get its Base64 string or a data URL ready to paste into HTML or CSS.
- Base64 to Image DecoderPaste Base64 or a data URL and see the picture it contains.
- Base64URL EncoderEncode text as URL-safe Base64 using - and _, with or without padding.
- File to Base64 ConverterPick any file and get its contents as a Base64 string.