Math & Numbers

Calculate the kinetic energy stored in a flywheel. E = ½·I·ω², ω = 2π·n/60. Enter the moment of inertia directly, or compute it from flywheel mass and radius (I = ½·m·r²). Supports J/kJ/Wh.

Math & Numbers

Calculate the gear ratio and output speed of a meshing gear pair. i = z₂/z₁ = n₁/n₂. Enter the tooth counts to get the ratio; add the driver speed to get the driven speed.

Math & Numbers

Calculate the overall ratio and output speed of a multi-stage gear train. i_total = i₁·i₂·…·iₙ (each i = z₂/z₁). Enter tooth pairs per stage and the input speed to get the final output speed.

Finance

Project today's amount (plus optional recurring contributions) forward with compound interest (FV). Supports a lump sum or lump sum + annuity, multiple compounding frequencies, a growth curve, and a per-period breakdown. FV = PV*(1+r)^n for a lump sum.

Health

See week-by-week fetal development from conception to birth (40 weeks). Enter your LMP date or a known gestational age and the tool highlights the current week with size, weight and milestones.

Utilities

Compute how to mix base fertilizers to hit a target N-P-K analysis like 10-10-10. Outputs per-fertilizer kg plus a parts ratio for any batch size.

Utilities

Identify a file by its magic-number byte signature, not the extension. Reads the uploaded file directly across ~70 types.

Design

Paste a Figma / Tokens Studio variables JSON and export to Tailwind, shadcn CSS variables, Style Dictionary, or SCSS. Preserves color, spacing and font tokens with type inference.

Math & Numbers

Convert between frequency and wavelength with selectable medium; results in all common frequency and length units

Math & Numbers

Compute distance, time, or final velocity for free fall from rest, given any one plus gravity

Math & Numbers

Compute force, mass, or acceleration from Newton's second law, with weight on Earth

Design

Calculate camera field of view from focal length and sensor size, with scene coverage at distance.