帆 胡

Trusty Calculator is a free library of 433 calculators for construction, finance, math, education, business, health, and unit conversion. Each tool aims to show the formula, assumptions, units, worked examples, and primary sources behind the result. No account is required.

Workshop Calc brings metal weight, unit and fraction conversion, tap drills, threads, bolt circles, chamfers, feeds and speeds, measurement over wires, and job records into one local-first iPhone and iPad app. It works without an account or ads, and core calculations are free with an optional one-time Pro unlock. Results are estimates; verify critical work against standards, manufacturer data, and qualified professionals.

ProfitSearcher turns noisy software-market data into actionable founder intelligence. It tracks breakout SaaS and App products, revenue and traffic signals, pricing changes, and unmet user needs, then publishes concise signals and deep-dive reports to help founders decide what to build.