Developer Tools
The daily friction of building software: formatting, cron syntax, API requests, JWT inspection, container registries. Each tool is small on purpose — you open it, get an answer, and close the tab.
Nothing here is a substitute for your test suite. They are for the moment when you need to see what a string actually contains before you write the test.
- API TesterOnline HTTP API tester: send GET/POST/PUT/DELETE requests with custom headers, query params and body, then generate curl, Python, Go or Java client code.
- Base Converter
- Base64 Encode and DecodeConvert text or files to Base64 and back. Supports the URL-safe variant and data URL prefixes; UTF-8 aware, so Chinese never turns into mojibake.
- Code Formatter
- Cron Expression Generator and ParserBuild cron expressions visually, or paste any expression to get a plain-language description, a field-by-field breakdown and the next 20 run times. Supports */N, N/M, a-b, a,b,c, plus L/W on the day field and L/# on the weekday field.
- cURL to CodeTurn a cURL command into request code for 49 languages and formats, including Python, Go, JavaScript and Rust, or output raw HTTP, HAR and JSON.
- Docker Mirror AcceleratorUsable mirrors for Docker Hub, GHCR, Quay, MCR, K8s, GCR, Elastic and NVCR, with a generated daemon.json or containerd config
- JWT Decoder
Guides in this category
Common questions
Do these tools send my code anywhere?
Formatting, encoding and inspection run in the browser. Tools that need a network round trip say so on the page.