What is Base64 encoding used for?

Base64 is used to transmit binary data (images, files, binary payloads) as plain text. Common uses: embedding images in HTML/CSS, JWT tokens, HTTP Basic Auth, email attachments (MIME).

Does Base64 encoding make data secure?

No. Base64 is encoding, not encryption. Anyone can easily decode it. Use encryption (AES, RSA) if you need security, not Base64.

Why is Base64 output longer than the input?

Base64 encodes every 3 bytes of input as 4 ASCII characters, which means encoded output is approximately 33% larger than the original.

What is the difference between standard and URL-safe Base64?

Standard Base64 uses + and / characters which have special meaning in URLs. URL-safe Base64 replaces them with - and _ so the encoded string is safe in URLs and filenames.

Outils de Développement

Encoder le texte au format Base64

Encodeur Base64

Encoder le texte au format Base64

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Encodage Base64

Texte à Encoder

Base64 Encodé

Learn more about Base64 Encoder

About Base64 Encoder

Encode text strings or binary data to Base64 format for safe transmission in URLs, JSON payloads, HTTP headers, and email. Base64 encodes arbitrary binary data as ASCII characters that work in any text-based protocol.

Key features

Encodes any text string to Base64
Handles UTF-8 and multibyte characters correctly
URL-safe Base64 variant available
Copy encoded result with one click
Instant encoding — no server needed

How to use Base64 Encoder

1Paste or type the text you want to encode
2The Base64 encoded result updates instantly
3Toggle URL-safe mode if needed (replaces + with - and / with _)
4Click "Copy" to copy the Base64 string

Frequently asked questions

What is Base64 encoding used for?: Base64 is used to transmit binary data (images, files, binary payloads) as plain text. Common uses: embedding images in HTML/CSS, JWT tokens, HTTP Basic Auth, email attachments (MIME).
Does Base64 encoding make data secure?: No. Base64 is encoding, not encryption. Anyone can easily decode it. Use encryption (AES, RSA) if you need security, not Base64.
Why is Base64 output longer than the input?: Base64 encodes every 3 bytes of input as 4 ASCII characters, which means encoded output is approximately 33% larger than the original.
What is the difference between standard and URL-safe Base64?: Standard Base64 uses + and / characters which have special meaning in URLs. URL-safe Base64 replaces them with - and _ so the encoded string is safe in URLs and filenames.