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Base64 encoder and Base64 decoder online
Encode and decode Unicode text with optional URL-safe output.
Base64 encoder and decoder
Base64 encoder and decoder
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Base64 encoder and decoder
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Base64 encoder and decoder
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Base64 encoder and decoder
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Base64 encoder and decoder
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Base64 encoder and decoder
Base64 encoder and decoder
Base64 encoder and decoder
Examples
Input text
Hello, World!
Base64
SGVsbG8sIFdvcmxkIQ==
Base64 Guides & articles
What Is Base64 Encoding, and Why Does Software Still Use It?
Base64 turns binary bytes into portable text. Understanding why it exists makes its odd-looking output, padding, overhead, and limitations much easier to reason about.
Read articleBase64 vs Base64URL: Similar Encodings With Different Jobs
Base64URL changes only a few characters, yet those changes matter whenever encoded data appears in URLs, cookies, filenames, or JWTs.
Read articleWhen Not to Use Base64: Performance, Security, and Design Trade-offs
Base64 is useful at text-only boundaries, but using it everywhere creates larger payloads, extra memory work, misleading security, and harder APIs.
Read articleRelated tools
Base64 encoder and Base64 decoder online is often used together with JWT decoder and JSON Web Token parser online, JSON formatter, JSON validator and JSON decoder online, URL encoder, URL decoder and query string parser when payloads, tokens, URLs, logs, or markup move through the same workflow.
JWT decoder and JSON Web Token parser online
Decode JWT header, payload and useful token metadata in the browser.
Open JWT decoder and JSON Web Token parser online JSONJSON formatter, JSON validator and JSON decoder online
Format, minify, validate, sort keys, copy and download JSON payloads.
Open JSON formatter, JSON validator and JSON decoder online URLURL encoder, URL decoder and query string parser
Encode values, decode query strings, and inspect URL parts and params.
Open URL encoder, URL decoder and query string parserBase64 encoder and decoder
Encode and decode Unicode text with optional URL-safe output. DevToolGrid Online offers a free Base64 encoder and Base64 decoder online.
What is Base64?
Base64 is an encoding scheme that represents binary data as ASCII text using 64 characters (A–Z, a–z, 0–9, + and /). It is widely used to embed images in CSS or HTML, carry binary data inside JSON or email, and store small files as text. Base64 is encoding, not encryption — it does not protect or hide data.
How to encode and decode Base64
- 1 Paste text into the input panel, or pick a file to encode.
- 2 Click Encode to convert to Base64, or Decode to read Base64 back.
- 3 Enable URL-safe if the value will be used in a URL or filename.
- 4 Copy the result, preview images, or download the decoded bytes.
Common Base64 mistakes
- Wrong paddingStandard Base64 is padded with = so its length is a multiple of 4. Removing or adding padding breaks decoding.
- Standard vs URL-safeURL-safe Base64 replaces + and / with - and _. Decoding URL-safe data with a standard decoder fails.
- Treating it as encryptionBase64 is fully reversible by anyone. Never use it to protect passwords or secrets.
Base64 vs Base64URL
Standard Base64 uses + and / and = padding, which are unsafe in URLs and filenames. Base64URL replaces + with -, / with _ and usually drops the padding, so the result is safe to place in query strings, JWTs and file names. This tool supports both with a single toggle.
FAQ
Is this tool free?
Yes. The Base64 encoder and decoder is completely free, with no sign-up or limits.
Is my data sent to a server?
No. Encoding and decoding run locally in your browser, so files and text never leave your device.
Can it encode files and images?
Yes. Drop a file to get Base64, build a data URI, and preview images directly in the browser.
What is URL-safe Base64?
A variant that uses - and _ instead of + and / so the value can be used safely in URLs, filenames and tokens.