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Popular Tools
Top tools our users love
Aspect Ratio Calculator
DesignFind the ratio of any width/height and resize proportionally.
HEX to RGB Converter
DesignConvert HEX color codes to RGB, HSL, and CSS values.
Character Counter
WritingCount characters with/without spaces, words, sentences in real time.
Token Counter
AI/DevEstimate GPT-5.5 and Claude token usage and API costs.
Age Calculator
UtilityCalculate exact age from birthday in years, months, days.
Unix Timestamp Converter
DevConvert Unix epoch timestamps to human-readable dates.
Roman Numeral Converter
MathConvert numbers to Roman numerals and back (1–3999).
Days Between Dates
UtilityCount days, weeks, months, and workdays between dates.
Instant Results
All calculations run locally in your browser. No server round-trips, no waiting. Results appear as you type.
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Your data never leaves your device. No cookies, no tracking, no analytics on your input. We can't see what you calculate.
Works Everywhere
Desktop, tablet, or phone. Any modern browser, any operating system. No app to install, no account to create.
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