Handy Online Tools for Software Developers
Privacy-first collection of converters, encoders, crypto, formatting, and network utilities. All calculations run securely in your browser with zero server transmission.
Most Popular Developer Tools
Base64 string encoder/decoder
Simply encode and decode strings into their base64 representation.
IPv4 subnet calculator
Parse your IPv4 CIDR blocks and get all the info you need about your subnet.
Docker run to Docker compose converter
Transforms "docker run" commands into docker-compose files!
Bcrypt
Hash and compare text string using bcrypt. Bcrypt is a password-hashing function based on the Blowfish cipher.
Chmod calculator
Compute your chmod permissions and commands with this online chmod calculator.
Crontab generator
Validate and generate crontab and get the human-readable description of the cron schedule.
Hash text
Hash a text string using the function you need : MD5, SHA1, SHA256, SHA224, SHA512, SHA384, SHA3 or RIPEMD160
Json Viewer
Online Json Viewer utility for software developers and IT engineers.
JWT parser
Parse and decode your JSON Web Token (jwt) and display its content.
Qr Code Generator
Online Qr Code Generator utility for software developers and IT engineers.
SQL prettify and format
Format and prettify your SQL queries online (it supports various SQL dialects).
UUIDs generator
A Universally Unique Identifier (UUID) is a 128-bit number used to identify information in computer systems. The number of possible UUIDs is 16^32, which is 2^128 or about 3.4x10^38 (which is a lot!).
Explore All Tool Categories
Crypto
Cryptography, hashing, key generation, and token generation tools running securely in your browser.
Converter
Instant data format, encoding, color, date, and case converters for modern engineering workflows.
Web
Web development utilities for HTTP headers, JWT tokens, URLs, meta tags, and browser inspection.
Images and videos
QR code generators, SVG placeholders, and webcam recording tools with zero server transmission.
Development
DevOps & development utilities including Docker compose, Cron generator, SQL/JSON/XML formatters.
Network
IP address calculators, CIDR subnet masks, MAC address lookup, and IPv6 ULA generators.
Measurement
Timers, chronometers, benchmark builders, and unit converters for engineering calculations.
Text
Text inspection, Diff checkers, Lorem Ipsum generators, string obfuscation, and ASCII banners.
Data
International phone number formatters, IBAN validation, and data verification instruments.
Why Software Engineers & IT Teams Trust sde.tools
When dealing with sensitive tokens, private certificates, production JSON data, or internal IP subnets, sending payloads to unknown third-party servers is a security hazard.
100% Client-Side Privacy
Every calculation, cryptographic hash, and data conversion happens directly inside your web browser. No network payloads or analytics on user input.
Blazing Fast Performance
Zero network round-trips. Instant real-time feedback as you type, with code-split bundles that keep initial page loads near instantaneous.
Offline Capable
All algorithms and utilities run fully offline once loaded. Bookmark your favorite tools and use them without an active internet connection.