Developer & API tools · 21 tools
Developer tools
that show their work.
JSON, JWT, base64, regex, UUIDs, hashing, and networking utilities — every tool explains what it's doing, not just a black-box output. Runs entirely in your browser. No signup, no data leaves your machine.
Live workbench
DeveloperWhy Utilix developer tools
See every step
Decoded output, structure, and worked examples sit beside the result — not a bare black-box answer.
Built for real work
JSON, JWT, hashing, and networking tools designed for actual debugging, not just a toy demo.
Private by default
Everything runs in your browser — no token, payload, or key you paste in ever leaves your machine.
Developer first
Start with a task
Pick a job-to-be-done. Each path opens a tool with clear, inspectable output and related utilities.
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Finance, AI cost, health, and everyday tools stay one click away.
Featured developer tools
Popular tools
- JWT DecoderDecode JSON Web Tokens to inspect header and payload JSON. Explains signature limits—client-side only; never paste production secrets you cannot rotate.
- JSON FormatterFormat, minify, sort keys, and validate JSON online free with readable errors. Fully client-side — no account, uploads, or remote storage.
- UUID GeneratorGenerate RFC-style UUID v4 and time-ordered v7 identifiers with formatting options. Fully client-side — no account, uploads, or remote storage.
- Regex TesterTest regular expressions against sample text with highlighted matches and capture groups. Fully client-side — no account, uploads, or remote storage.
- Hash GeneratorCompute common digests in hex from any text. Fully client-side — no account, uploads, or remote storage. Runs locally in your browser.
- Base64 Encode / DecodeEncode or decode Base64 with UTF-8-safe handling for Unicode, emojis, and binary payloads. Runs locally in your browser.
- JSON ↔ YAML ConverterConvert between JSON and YAML with readable formatting and error messages. Fully client-side — no account, uploads, or remote storage.
- Cron Expression ExplainerParse five-field cron expressions into human-readable schedules and upcoming run times. Fully client-side — no account, uploads, or remote storage.
Learn
Money guides that pair with the tools
What Is a Subnet Mask? Explained With Examples
What a subnet mask is, how 255.255.255.0 and /24 work, a worked network-address example, a mask-to-CIDR table, and how to choose the right mask.
Developer toolsMAC Address Vendor Lookup: How OUI Lookup Works
Find who made a device from its MAC address: how OUI prefixes work, MA-L/MA-M/MA-S blocks, and why randomized or local MACs return no vendor.
Developer toolsWhat Is CIDR? IP Address Notation Explained
Learn CIDR notation (/24, /16, /8), how prefix length maps to subnet masks, usable host counts, and why CIDR replaced classful IP addressing.
Developer toolsHow Subnetting Works: Step-by-Step Guide
Subnetting explained: network vs host bits, calculating network and broadcast addresses, splitting CIDR blocks, and choosing the right subnet size.