Regex Tester
Test JavaScript regular expressions against sample text with live matches, groups and replace.
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The everyday utilities, in one place
The grab-bag: a regex tester with live match groups, a cron expression explained in English with its next run times, chmod bits you can toggle, base and unit conversions, an ASCII table you do not have to search for.
These are the tools you open ten times a day and close again in twenty seconds, so they load fast and work offline once the page has been visited.
15 Developer Utilities tools
ASCII / Unicode Inspector
Inspect each character: code point, UTF-8/UTF-16 bytes and HTML entity, locally.
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Smart Paste
Paste anything, it detects the format (JWT, JSON, SQL, XML…) and sends it to the right tool.
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Data Size Converter
Convert between bytes, KB/MB/GB/TB, binary KiB/MiB/GiB and bits, locally.
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Number Base Converter
Convert integers between hex, decimal, binary, octal and any base (2–36), locally.
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ASCII Table
Browse the full ASCII table with decimal, hex, octal and binary codes, locally.
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Roman Numeral Converter
Convert between integers (1–3999) and Roman numerals, locally.
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Temperature Converter
Convert temperatures between Celsius, Fahrenheit, Kelvin and Rankine, locally.
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Chmod Calculator
Toggle Unix read/write/execute bits and get the octal and symbolic chmod, locally.
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Docker Run to Compose
Convert a `docker run` command into a docker-compose service definition, locally.
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Percentage Calculator
Percent of a value, what-percent-of, and percentage change — all in one, locally.
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ETA Calculator
Estimate how long a task takes and when it finishes from a measured rate, locally.
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Benchmark Builder
Compare timing samples across suites by mean and variance, then export the results, locally.
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Chronometer
A simple stopwatch with laps, running locally in your browser.
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Git Cheatsheet
A searchable memo of the git commands you keep forgetting, locally.
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