Encoding
Base64 Encode / Decode
Encode text to Base64 or decode Base64 back to UTF-8 text in your browser.
Focused calculator
Calculate Base64 Encode / Decode
SGVsbG8sIENvbnZlbWF0aWsh
When to use this tool
Use the Base64 Encode / Decode for quick, focused data cleanup directly on the page before copying the output into code, documentation, spreadsheets or another tool.
- Developer, SEO, analytics and content workflows where text needs to be encoded, decoded or normalized safely.
- Cleaning a value before pasting it into a URL, HTML page, config file or API request.
- Checking privacy notes before using sensitive text such as tokens or copied session data.
Accuracy, privacy and assumptions
- Encoding changes representation, not meaning. Decoding untrusted input can reveal unsafe HTML, URLs or scripts.
- Browser-only tools keep input local; API-enabled tools can also be called programmatically for non-sensitive data.
Common mistakes to avoid
Most wrong answers from a Base64 Encode / Decode come from unit direction, rounding too early, or copying a result without its original context.
- Do not assume encoding encrypts data. Base64, URL encoding and HTML entities are reversible representations.
- Decode untrusted strings carefully because the output can contain scripts, markup or control characters.
- For private tokens or session strings, prefer browser-only tools and avoid unnecessary sharing.
Copy-ready result format
Base64 Encode / Decode output: SGVsbG8sIENvbnZlbWF0aWsh (Encoded from: Hello, Convematik!).
- Keep the original input available until the destination accepts the transformed output.
- Copy validation errors along with the input when debugging a failed import.
- Use browser-only pages for sensitive copied text or account-like payloads.
Best workflow for Base64 Encode / Decode
- Paste or type the input into the tool above.
- Choose the target mode or format when the tool offers one.
- Review validation errors and copy the output only after it matches the expected structure.
- For sensitive data, prefer browser-only tools and avoid API-enabled endpoints.
Next steps after this result
After the immediate calculation, choose the next tool based on what you plan to do with the value.
- Copy the transformed output into the destination and test it there.
- Keep a copy of the original input.
- Use browser-only pages for sensitive values.
Formula
How it works: Base64 maps every 3 bytes of UTF-8 data onto 4 ASCII characters from A-Z a-z 0-9 + /, padding with =. Decoding reverses the mapping.
Common examples
| Input | Result |
|---|---|
| Hello → encode | SGVsbG8= |
| U29s → decode | Sol |
| encode: 🚀 | 8J+agA== |
JSON API example
POST a JSON body to the public endpoint.
curl -X POST https://api.convematik.com/base64 \
-H 'Content-Type: application/json' \
-d '{"text": "Hello", "mode": "encode"}'
{
"result": "SGVsbG8="
}Common questions
What does the Base64 Encode / Decode do?
Encode text to Base64 or decode Base64 back to UTF-8 text in your browser.
Does the Base64 Encode / Decode send my data to a server?
The Base64 Encode / Decode runs locally in your browser for instant results, and the same transform is also available as a public JSON API endpoint.
When should I use the Base64 Encode / Decode instead of a spreadsheet or script?
Use the Base64 Encode / Decode for quick validation, formatting, decoding or cleanup when you need a deterministic output before copying the result into code, docs, an API request or a spreadsheet.
Is the Base64 Encode / Decode free to use?
Yes. The Base64 Encode / Decode is free and does not require an account.