Free & browser-based

Developer & security tools,
no install required

Simple browser-based utilities for developers and security engineers. Nothing you enter ever leaves your browser.

Base64 Encoder & Decoder

Encode and decode Base64 text instantly, right in your browser.

Open Tool
JWT Decoder

Decode and inspect JSON Web Tokens — header, payload, and signature.

Open Tool
JSON Formatter

Pretty-print, validate, and minify JSON in one click.

Open Tool
Hash Generator Coming Soon

Generate MD5, SHA-1, and SHA-256 hashes from text or files.

CIDR Calculator Coming Soon

Calculate subnet ranges, host counts, and IP blocks from CIDR notation.

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Free Developer & Security Tools

DevSecBox is a collection of free, browser-based utilities for developers and security engineers. Every tool runs entirely on the client side, so text and files you enter are processed locally and never uploaded to a server.

Why use browser-based tools?

Because everything runs in your browser, DevSecBox tools are fast, work offline once loaded, and keep your data private — nothing you paste or type is transmitted or stored anywhere. This makes them safe to use even with sensitive tokens, keys, or internal data.