About
About this site
Karu Tools is a free collection of browser-based utilities for everyday tasks — counting characters, calculating ages, splitting bills, and more. No sign-up required; just open and use.
Tool Categories
Text
Tools for working with writing, strings, and input text.
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Date and time
Tools for checking dates, differences, and Japanese era names.
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Developer and data
Utilities for development, data formatting, and identifiers.
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Lottery and decisions
Tools for random picks, drawing lots, and lightweight decisions.
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Everyday
Tools for everyday preparation, shopping, and quick calculations.
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Music and audio
Tools for music practice and audio processing.
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Disclaimer: Tool results are intended for general checking. For important decisions, compare the result with your source data or official information.