Base64 Tool
Encode and decode Base64 locally for quick text handling.
What is Base64 Encoding?
Base64 turns binary data into text so it can travel through email, HTML, JSON, URLs, and other text-only systems. It is commonly used by developers to embed small files inline, debug API payloads, and inspect JWT tokens. It is a transport format, not protection, so never rely on it to hide sensitive information.
Benefits: Encode or decode text and binary data, supports UTF-8, local-only processing, no upload step, instant conversion with no size throttling, and one-click clipboard copy for fast workflow integration.
Best for: Data URIs, JWT debugging, email transport, moving text through text-only systems, embedding small images in CSS or HTML, and inspecting API request and response bodies.
Limitations and tradeoffs
- Base64 is encoding, not encryption, so sensitive data should not be treated as protected.
- Very large binary payloads can cause high memory usage in the browser.
- Malformed or partial strings can decode with errors depending on source validity.
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Browse Developer toolsQuestions before you use it
Is Base64 the same as encryption?
No. Base64 is encoding, not encryption. Anyone can decode it. Use proper encryption for sensitive data.
Why does Base64 output end with '=='?
Base64 uses padding characters ('=') to ensure output length is a multiple of 4.
Is my data safe?
Completely. All processing happens locally in your browser. Nothing is sent to any server.
Why is the Base64 output larger than the original?
Base64 encoding increases data size by roughly 33% because it represents every 3 bytes of input as 4 ASCII characters. This trade-off is expected and is the cost of making binary data safe for text-only channels like JSON, HTML, or email headers.
Can I use this tool to encode images as data URIs?
Yes. You can paste the raw binary content or use a file reader to get the Base64 string, then prepend the appropriate MIME prefix such as data:image/png;base64, to create a valid data URI. This is useful for embedding small icons or thumbnails directly in HTML or CSS without extra network requests.