Useful tools
Tools
A small collection of practical utility apps for work, study, and everyday use.
cardcounter.pairusuo.top
Card Counter
A lightweight browser card counter for quick blackjack practice and table-side drills.
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clock.pairusuo.top
Desktop Clock
A clean fullscreen clock page for work setups, study sessions, and secondary displays.
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roi-calculator.pairusuo.top
Keyword ROI Calculator
A simple ROI calculator for evaluating keyword traffic value before you spend on SEO or ads.
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data-table.pairusuo.top
Data-table
tools.descriptions.dataTable
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More tools on the way
More practical calculators and small utilities will be added over time.