Base64
Base64のエンコード／デコード。
Interactive controls load with JavaScript. Processing stays in your browser—nothing is uploaded.
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How to use
- Open Base64 tool — Open the encode/decode page.
- Paste text — Paste plain text or Base64 into the input.
- Encode or decode — Run encode or decode. Confirm standard vs URL-safe alphabet if needed.
- Copy output — Copy the result for APIs, data URLs, or debugging.
Limits
Encoding is reversible and not secret. Invalid padding or alphabet mismatches cause errors.
When to use
Embed small binaries in text protocols or inspect data URLs—without uploading secrets.
When not to use
When you need encryption, hashing for passwords, or streaming huge files.
Privacy note
All encode/decode steps stay on-device.
References
FAQ（5）
Is Base64 encryption?
No. Base64 is encoding for binary-safe text (see RFC 4648). Anyone can decode it—do not treat it as secrecy.
Why do I see “Invalid Base64”?
Check padding (=), remove spaces/newlines, and confirm the alphabet (standard vs URL-safe).
Does Unicode text encode correctly?
Yes. Text is handled as UTF-8 before encoding and after decoding.
Is data sent to your servers?
Never. Encode/decode stays on your device.
When should I use Base64?
Embedding small binaries in JSON/HTML, data URLs, or protocols that only accept text—not for protecting secrets.