Confidence Interval Calculator - Online Mean & Proportion
Compute confidence intervals for a population mean (known/unknown sigma) and proportion. All popular Z/T values. Local.
UD5 Toolkit
Add, subtract, multiply, and divide fractions online — with steps, mixed numbers, and simplified results.
Compute confidence intervals for a population mean (known/unknown sigma) and proportion. All popular Z/T values. Local.
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Press any key combination and record the sequence. Export as JSON or human‑readable text. Perfect for documenting shortcuts.
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Play a virtual piano keyboard using mouse or computer keys. Sustain and octave control. Record and play back your tune.
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Hash any text using simple, fast algorithms: DJB2, SDBM, or CRC32. Get integer or hex. For quick lookups. Local.
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Record the empty weight of your carboys and kegs. Then weigh a full one to instantly get the liquid weight and volume. Eliminate guesswork.
Enter a URL and trace the full redirect chain, seeing each hop's status code and location. Identify unnecessary redirects. Client-side fetch.