DevCoreTools

Base64 Encoder and Decoder

Encode text to Base64, decode Base64 strings, convert between Base64 and Base64URL, and validate encoded data.

Plain text input

Enter UTF-8 text to encode.

Processed locally in your browser Limit 200,000 characters. Your input is processed in your browser and is not uploaded or sent to a server. Avoid pasting production secrets, access tokens, private keys, passwords, or sensitive customer data unless you understand the risk.
0 / 200,000 characters0 input bytes

Base64 output

Read-only result

Output appears here as you type.
0 output characters0 output bytes

What is Base64 encoding?

Base64 represents binary data using a limited set of text characters. It is commonly used in data URLs, email attachments, API payloads, certificates, and tokens where raw bytes cannot be transported directly.

How to encode text to Base64

  1. Select Encode and choose Standard Base64 or Base64URL.
  2. Enter or paste UTF-8 text in the input panel.
  3. Copy or download the generated output.

How to decode Base64

  1. Select Decode and choose the format used by your value.
  2. Paste the encoded text. Spaces and line breaks are ignored.
  3. Review and copy the decoded UTF-8 text.

Base64 vs Base64URL

Standard Base64 uses + and /. Base64URL replaces them with - and _ so values are safer in URLs and filenames. Base64URL padding is often omitted.

Common Base64 use cases

Base64 is used for small transport-safe values, data URLs, API payloads, HTTP Basic authentication credentials, JWT header and payload segments, configuration values, email attachments, and debugging encoded strings.

What is Base64 padding?

Base64 output is arranged in groups of four characters. One or two trailing = characters may be added when the final group is incomplete. For example, SGVsbG8= and the unpadded SGVsbG8 both represent Hello. Standard Base64 commonly keeps padding, while Base64URL values such as JWT parts often omit it.

Is Base64 encryption?

No. Base64 is reversible encoding and provides no secrecy, integrity, or authentication. Anyone with the encoded value can decode it, so do not use Base64 to protect passwords, API keys, or private data.

Unicode and UTF-8 support

This tool converts text using UTF-8, so accented characters, non-Latin writing systems, and emoji can be encoded and decoded correctly.

Keep working

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Coming soon

URL Encoder/DecoderComing soonEncode and decode URL components and query-string values.

Frequently asked questions

Is this Base64 tool free?

Yes. It is free to use and requires no account.

Is my text uploaded?

No. Encoding and decoding happen entirely in your browser.

Can this tool encode Unicode and emoji?

Yes. Input text is converted using UTF-8 before Base64 encoding.

Why does Base64 sometimes end with equals signs?

The = characters pad the final group to a complete Base64 block. Some formats, especially Base64URL, omit this padding.

Why is my Base64 value invalid?

It may contain characters from the other Base64 variant, have malformed padding, or decode to bytes that are not valid UTF-8 text.

Does Base64 make data secure?

No. Base64 only changes representation and should not be treated as encryption.

Can I use this for JWTs?

Yes. JWT header and payload parts use Base64URL encoding. For complete claim and timing inspection, use the JWT Decoder.