AllTools.dev is a modern, fast, free online toolkit built for people who need quick, accurate calculators and converters without signing up, creating an account, or wading through cluttered interfaces. The platform offers 500+ tools across finance (mortgage calculators, loan amortization, compound interest, currency conversion, debt payoff, retirement planning), health (BMI, calorie needs, pregnancy tracking, ideal weight, body composition), math (scientific, statistical, geometric, percentage, fraction), science and engineering, date and time utilities, unit conversions (volume, length, temperature, power, area), developer utilities (JSON, regex, JWT, hashing), and interactive math and algorithm visualizations. Every tool is free and works instantly in the browser. No accounts, no paywalls, no sign-in walls, no data collection beyond standard analytics. Calculations happen client-side for speed and privacy. Unlike older established calculator sites that grew through 20 years of ad-heavy layouts and outdated UX, AllTools.dev is built fresh on Astro with a clean, mobile-first, accessibility-conscious interface. New calculators ship weekly based on user demand. Ideal for: students doing homework, developers needing quick conversions, finance-minded folks planning loans and investments, professionals doing scientific or engineering calculations, and anyone who just needs a fast answer without installing an app.

RepDB is a one-time-purchase exercise dataset for developers building fitness and workout apps — not a subscription, not a rate-limited API. You download the data once and own it: JSON (and SQLite on the higher tier), WebP images, and full EN/DE/ES translations, with no per-request billing and no dependency on our servers staying up.

A free tier includes 400 exercises with flat-style 512×512 images, attribution-licensed for commercial in-app use. The Starter tier ($199) adds the full catalog in classic white-background style. Standard ($399) adds transparent 1024px images, looping animations, exercise relations (similar/progressions/regressions), workout templates, and embeddings — exclusive to that tier.

Every exercise includes muscle-group highlighting, equipment/muscle icons, MET values, and safety/goal tags. Compared to GIF- or JPG-based competitor APIs, RepDB images are transparent WebP with no watermarks, so they drop into any app UI without a white box around them.