Base64 Encoder / Decoder
Encode and decode UTF-8 Base64 text locally.
Convert text to Base64 and decode Base64 back to UTF-8 text in your browser. The tool uses TextEncoder and TextDecoder so CJK text, accents, and emoji work correctly.
Tool area
How to use
- Paste plain text or a Base64 string into the input box.
- Press Encode to convert text to Base64.
- Press Decode to convert Base64 back to text.
- If decoding fails, check that the input is valid Base64.
Use cases
- Create Base64 snippets for configuration examples or test data.
- Inspect Base64 strings from documentation or API responses.
- Handle UTF-8 text that includes Chinese, accents, or emoji.
Content and verification review:
How to verify a Base64 Encoder / Decoder result before relying on it
This is a reproducible review method, not another list of button instructions. Start with a small baseline whose answer you can predict, test one boundary condition, and only then use real material. Line endings, Unicode, punctuation, encoding, and destination-platform rules can change how the same text is counted, cleaned, or formatted.
Establish a predictable baseline
Use “Create Base64 snippets for configuration examples or test data.” as the first test case. Begin with “Paste plain text or a Base64 string into the input box.” and write down the expected result before clicking anything. If the output differs, check units, formatting, whitespace, file page count, and selected options before assuming either the tool or source data is correct.
Probe an edge or failure case
For a second run, adapt “Inspect Base64 strings from documentation or API responses.” and deliberately include one empty value, extreme value, duplicate, unusual character, large file, or unsupported format. The relevant boundary is: Base64 changes representation rather than securing data and typically increases size by roughly one third. This tells you when the page should be used as a draft aid rather than the final authority.
Cross-check before acceptance
The page is designed to “Encode and decode UTF-8 Base64 text locally..” Write down the output you expect before running it; this makes format and setting errors easier to spot. If the result will be shared, imported elsewhere, used to replace an original file, or affect money or grades, also complete the final action “If decoding fails, check that the input is valid Base64..” Keep the input assumptions and untouched source so another person can reproduce the decision later.
Acceptance checklist
- Input: confirm that the source, units, timezone, encoding, or file format matches the fields on Base64 Encoder / Decoder.
- Process: run one small case you can judge independently, followed by one likely edge case.
- Output: compare counts, pages, dimensions, totals, timing, or format, and reopen any downloaded file.
- Decision: retain the source and verify important output against official rules, the destination system, or a second method.
Who is it for
- Developers inspecting APIs, configuration files, and data URIs
- QA teams testing Unicode text and transport formats
- Students learning the difference between encoding and encryption
Real examples
Inspect a Base64 value from an API
Decode a short value from a trusted source and confirm that the result is expected UTF-8 text. Base64 can represent arbitrary binary data, so this text-focused tool reports an error instead of treating every byte sequence as readable content.
Create a documentation example
Encode a non-secret sample and immediately decode it to verify a round trip. Never use Base64 to hide API keys, passwords, or personal data because anyone can reverse it without a key.
Good to know
- Base64 changes representation rather than securing data and typically increases size by roughly one third.
- This page is designed for UTF-8 text, not arbitrary binary file conversion.
- Avoid accidental spaces or line breaks when copying output because some receivers validate Base64 strictly.
FAQ
- Does this support non-English text?
- Yes. Text is converted through UTF-8 bytes before Base64 encoding, so CJK text and emoji work correctly.
- Is Base64 encryption?
- No. Base64 is an encoding format, not encryption. Anyone can decode it.
- Why did decoding fail?
- The input may not be valid Base64, or the decoded bytes may not be valid UTF-8 text.
Privacy & local processing
🔒 This tool runs entirely in your browser. No data is uploaded to any server.
This tool runs mainly in your browser. The content you enter is not sent to FunnyTools servers.
Trust & usage note
This tool runs mainly in your browser. Your input is not actively uploaded to a server. Avoid entering highly sensitive data. Results are for reference only.
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