Calculator Center

What it does

Most online calculators just spit out a number. Calculator Center shows you the formula, the assumptions, and every step — so you can trust the result and learn from it. 29 free calculators across construction, math, finance, and everyday life. No sign-up. No ads. No black boxes. What makes it different: • Every calculator explains the formula it uses • Worked examples show how inputs map to outputs • Unit conversions follow NIST standards • Reviewed and updated by an editorial team

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  CalculatorNinjas2024 · ▲117

  Ultimate online calculator for finance, health, stats & Math

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  Webacus2022 · ▲106

  Swiss-army knife for developers

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  Calculator Notepad2022 · ▲75

  A free-form calculator for Chrome

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  Online Calculator Tools20d ago · onlinecalculatortools.com · ▲1

  150+ free calculators for everyday decisions

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  Free Online Calculators25d ago · calculatorpath.com · ▲3

  Free Online Calculators - Math, Finance, Fitness & More

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  Calculator Castle 12d ago · calculatorcastle.com · ▲2

  242 free calculators, no signup, answer in one screen

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  PaymentKit▲466

  Billing that survives a processor shutdown

  Commerce · 13d ago · paymentkit.com

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  Equitybee Benchmark▲241

  Compare your startup equity grant for free.

  Commerce · 26d ago · equitybee.com

• TL
  The load-bearing vocabulary of Claude▲703

  Life & fun · 10d ago · louisabraham.github.io

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  Hey Noah▲641

  A proactive AI executive assistant for founders

  AI · Aug 2026 · heynoah.io

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  Clipto MCP▲640

  Let agents source clips from terabytes of your local video

  Work · 18d ago · clipto.com

• SA
  Simple algorithm and color space to generate diverse skin tones▲627

  Hello HN! I found that picking out plausible but diverse skin tones for my digital art and game development projects was kind of difficult, and I got curious about if there was a way to define a color space that made it easy. I've built a color picker and procedural generation algorithm based on the space as well as a bunch of other fun js features and demos throughout the page that use the equations. If you find it interesting, I have lots of explanations of how I built it and what properties the space has. The methodology might be a bit shaky, but hopefully the result is as helpful for…

  Life & fun · Aug 2026 · toneyalexander.github.io

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  AdAnt AI▲608

  Claude for viral, high-converting social ads

  AI · Aug 2026 · adant.ai

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  I trained a 125M model to autocomplete piano on-device▲598

  I trained a 125M-parameter transformer to autocomplete piano performances in real time (~108 notes/sec on an iPhone 15). The idea is basically GitHub Copilot or Tabnine, except instead of prompting it with code, you prompt it by playing a few notes on a MIDI piano. The model then continues what you played, entirely on-device. The app is free if anyone wants to try it. Happy to answer questions about the model, training, Core ML, or the many things that didn't work.

  AI · 17d ago · simedw.com