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Data & JSON
6JSON Formatter
Beautify, validate and minify JSON instantly.
Data Format Converter
Convert between JSON, YAML, TOML, XML and CSV.
Semantic JSON Diff
Compare two JSON objects and show what really changed.
JSON → Types
Generate Go, Rust, Python or TS types from a JSON.
JSONPath / jq
Query and filter a JSON with JSONPath expressions.
JSON Key Case
Switch keys between snake_case and camelCase.
Security & Crypto
5X.509 Certificate Decoder
Read an SSL/PEM certificate: validity, issuer and SAN.
JWT Decoder
Decode a JWT token and read its contents.
Key Pair Generator
Create SSH keys and RSA or Ed25519 pairs.
Hash Generator
Compute SHA-1, SHA-256, SHA-384 and SHA-512 hashes.
UUID / ULID
Generate unique UUID and ULID identifiers.
Text & Encoding
3Numbers
1API & Network · Workers
6Webhook Tester
Receive and inspect webhooks on a unique URL.
Mock API
Create a test JSON endpoint instantly.
DNS / WHOIS
Look up DNS records and WHOIS data for a domain.
HTTP Headers
Inspect the HTTP headers and redirect chain.
SSL/TLS Check
Check a domain's SSL/TLS certificate.
HAR Analyzer
Analyze a HAR file and find the slowest requests.
Code & Conversion
1Time
1Reference
8HTTP Status Codes
What each HTTP code means (404, 500…).
chmod Calculator
Work out Unix file permissions (chmod).
MIME Types
Find the MIME type for each file extension.
ASCII Table
ASCII table with decimal, hexadecimal and binary.
Common Ports
Which service uses each port (22, 80, 443…).
Key Code Finder
Find the JS code for any key.
Regex Cheatsheet
Quick guide to regex symbols and patterns.
Crontab Syntax
How to write cron expressions (crontab).