Random Utils
Calculators, visualizers, and tools — all in one place.
Retirement Calculator
Monte Carlo simulation across 1,000 market scenarios — see the probability your portfolio lasts.
Car Loan vs. Cash
Find out if a low-interest car loan beats paying cash by investing the principal.
Mortgage Amortization
Calculate monthly payments, total interest, and see how extra payments shorten your loan.
Compound Interest
See how investments grow over time with compounding and optional monthly contributions.
Unit Converter
Convert between SI and imperial units for length, mass, temperature, volume, area, and speed.
Lumber Cut Calculator
Plan woodworking cuts by cross-section. Get an optimized board cutting plan with minimal waste.
Tone Generator
Generate reference pitches for tuning instruments. Pick any note and octave — rich harmonic tone, works offline.
Guitar Tuner
Tune your guitar by ear or with your microphone. Play reference tones for each string and see real-time pitch detection.
Lumber & Screw Reference
Nominal vs. actual lumber dimensions plus screw pilot-hole drill bit sizes for softwood and hardwood — imperial and metric.
Chord Reference
Look up chord notes and fingerings for any root and chord type — major, minor, 7ths, diminished, and more. Piano and guitar diagrams with audio playback.
QR Code Encoder / Decoder
Generate QR codes from freeform text with version and error-correction control, or scan a QR code live using your device camera.
Website Theming Tool
Generate a complete set of CSS custom properties from a primary hue and saturation — complementary secondary palette, button colors, backgrounds, and success/error status colors.