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Inspector security/base64-encode

Base64 Encode

Overview

Base64 Encode turns text into the Base64 ASCII that MIME email, data URIs, JSON payloads and HTTP Basic Authorization headers require. The two panes are linked: type plain text on one side and the Base64 appears on the other, edit the Base64 and the text follows — so encoding and decoding sit on one screen with no mode to switch, and you can read the round trip before you copy. Both alphabets are available: standard, and the URL-safe variant that writes - and _ in place of + and /. Text is encoded as UTF-8 first, so accented letters, non-Latin scripts and emoji come through intact rather than throwing the error that browser-native btoa raises above U+00FF. Nothing is uploaded; the conversion happens in your browser.

HTTP Basic AuthorizationEncode a username:password pair into the Base64 that an Authorization: Basic header carries, without pasting the credentials into a web service that keeps them.
Values That Must Survive JSON or XMLEncode a multi-line string or an awkward payload so it can sit as a plain string value, with no escaping rules to get wrong.
Base64url for TokensSwitch to the URL-safe alphabet to produce the - and _ form that JWT segments and many APIs expect, rather than hand-editing a standard string afterwards.
Checking the Round TripBoth panes stay on screen, so you can confirm the Base64 decodes back to exactly what you meant before pasting it into a config file or a request.
Text That Is Not Latin-1Encode Cyrillic, CJK, Arabic or emoji content that a btoa-based encoder refuses outright, and get bytes the other side can decode back to the same characters.

Set

Security Tools 26

Neighbours

01 AES File & Text Encryptor 02 Base64 Decode 03 CSR Generator 04 DER to PEM Converter 05 Hash Generator 06 JWT Sign

Specification

Command: security.base64_encode
Set: Security
Input: text
Output: —
Max file: no limit
Batch: single file

Runtime

Engine: WebCrypto · OpenPGP.js
Threads: single
Isolated: —
WebGPU: —
Memory: —

Transport 0 B

The file is opened, worked on and written back inside this tab. No upload step exists in this tool — there is nowhere for the bytes to go.

Keys

Search: ⌘K
Panels: ⌘1 · ⌘2
Full width: F
All keys: ⌘/

How it works

Type into either pane

Plain text on one side, Base64 on the other. Editing either pane updates the other, so encoding and decoding happen on the same screen with no mode to switch.

Pick the alphabet

Standard Base64, or the URL-safe alphabet that uses - and _ in place of + and /. Any Unicode text works, emoji included.

Copy the result

Both panes stay on screen, so you can read the round trip before you copy. The conversion runs in your browser; nothing is uploaded.

Frequently asked

What is Base64 encoding used for?

It rewrites arbitrary bytes as a small set of ASCII characters, so they can travel through channels that only carry text: MIME email, JSON and XML string values, data URIs, and HTTP Basic Authorization headers. It is an encoding, not encryption — anyone can decode it, and it hides nothing.

Is my data secure during encoding?

The conversion happens in your browser. What you type is not sent to a server and is not stored, so an API key or a certificate fragment can be encoded here without handing it to an online service.

Does Unicode text encode correctly?

Yes. Text is read as UTF-8 first, so accented letters, non-Latin scripts and emoji all survive the round trip. Encoders built on the browser's btoa function fail on anything above U+00FF; this one does not use it.

Which alphabet should I pick?

Standard Base64 uses + and /, both of which mean something else inside a URL or a filename. The URL-safe alphabet writes - and _ in their place and is what JWT segments and many APIs use. The underlying bytes are identical; pick whichever the receiving system expects.

Keys

Search: ⌘K
Panels: ⌘1 · ⌘2
Full width: F
All keys: ⌘/

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