Anvil Tools
URL Encoder & Decoder
Encode text for a URL or decode percent-encoded values safely.
Open tool →Base64 Encoder & Decoder
Encode UTF-8 text as standard Base64, or decode a standard Base64 value back to text. This tool does not accept binary files. URL-safe Base64 uses a different alphabet; use the JWT Decoder for JWT header and payload sections.
Encode or decode Base64
Check a text round trip
This tool encodes UTF-8 text using standard Base64. Standard Base64 can include +, /, and =; it is not automatically safe as an unescaped URL parameter. Base64url uses a different alphabet. Neither form encrypts its contents.
| Input or check | Expected result or decision |
|---|---|
| Hello | SGVsbG8= |
| café | Y2Fmw6k= |
| Decode either output | The original text returns; arbitrary binary files are outside this text-only tool. |
| UTF-8 text: café 🙂 | Y2Fmw6kg8J+Zgg== → decoding returns café 🙂 exactly, including one space. |
How it works
- Paste plain text and click encode to get its Base64 representation.
- Paste a Base64 string and click decode to recover the original text.
- Unicode text, including accented characters and emoji, is handled correctly in both directions.
Common uses
- Embedding a small piece of data inside a URL or config value.
- Decoding a Base64-encoded token or payload while debugging an API.
- Preparing text for systems that only accept plain ASCII characters.
Your privacy matters here: check the FAQ below for exactly what happens to anything you enter into this tool.
Try a Unicode round trip
Encode a short sentence containing an emoji, then decode the result. You should get the original sentence back. Base64 is an encoding, not encryption: anyone with the output can decode it.
A practical walkthrough
- Encode a short test string such as Hello, then decode the output to check that it returns the original text.
- Preserve padding and character case when copying encoded data between systems.
- Use Copy to copy the output, and test the reverse operation to check that your text is preserved.
Tips for a reliable result
Base64 is an encoding, not encryption. Anyone who receives the encoded value can decode it; do not use it to hide credentials.
What to use next
These tools open separately; inputs are not transferred.
JWT Decoder
Inspect a JWT header and payload without uploading the token.
Open tool →Hash Generator
Generate SHA-256, SHA-384, or SHA-512 hashes from UTF-8 text.
Open tool →CSV to JSON Converter
Convert quoted CSV data into JSON arrays or objects locally.
Open tool →How this tool handles your data
Text is encoded or decoded in your browser and is not sent to an Anvil processing server.
Known limitations
Base64 is an encoding, not encryption. This tool is for text, and malformed input, variant alphabets, or binary file workflows may require a dedicated decoder.
Related guide and Lab test
Questions and troubleshooting
Is Base64 encryption?
No. Base64 is an encoding, not encryption — anyone can decode it back to the original text. Don't use it to protect sensitive information.
Why did decoding fail?
The input wasn't valid Base64, often because of extra whitespace, line breaks, or characters outside the Base64 alphabet.
Does this work with files, not just text?
This tool handles text input and output. For encoding files, a dedicated file-to-Base64 tool is a better fit.
When Base64 decoding fails
Check that the input is complete standard Base64 rather than a Base64url token segment or a copied filename. Arbitrary binary bytes may not decode as UTF-8 text. Use the JWT Decoder for token inspection and a file-capable decoder for binary documents.
Can Base64 protect confidential text?
No. It is a reversible representation, not encryption. Do not share a Base64 value if the original text contains a secret.
Why does a JWT section fail in a standard Base64 decoder?
JWTs use Base64URL, which differs in its alphabet and padding conventions. Use the JWT Decoder for token headers and payloads; decoding does not verify their authenticity.
Read the practical guide
Debug API Data with JSON, Base64, and Browser Tools
Work through JSON types, encoding, URL components, JWT claims, hashes, CSV conversion, and timestamps with small reproducible examples.