Developer Utilities
Small developer utilities that save a trip to a random website. Encode and decode Base64, explain a regex, build UTM links, generate QR codes and vCards, and more — the everyday helpers. Free in your browser, and available by API when you need them in a script.
Developer Utilities
Roofing felt underlayment calculator
rolls from area and coverage free
POST /home/roofing-felt$0.002Developer Utilities
Spray foam insulation calculator
board feet & kits from area and R
POST /home/spray-foam$0.002Developer Utilities
Stair headroom calculator
floor-to-floor, angle and opening vs code
POST /home/stair-headroom$0.002Developer Utilities
Stair stringer length calculator
diagonal cut from rise and run
POST /home/stair-stringer-length$0.002Developer Utilities
Starter strip shingle calculator
pieces for eaves and rakes
POST /home/starter-shingles$0.002Developer Utilities
Tile spacer calculator
estimate spacers from tile count and corners
POST /home/tile-spacers$0.002Developer Utilities
TPO membrane roll calculator
rolls from roof area, size and seam overlap
POST /home/tpo-membrane$0.002Developer Utilities
Trim paint calculator
quarts and gallons from linear feet and width
POST /home/trim-paint$0.002Developer Utilities
Vinyl plank flooring calculator
boxes from room area, coverage and waste
POST /home/vinyl-plank$0.002Developer Utilities
Wall plate lumber calculator
LF & boards (bottom 1 + top 2)
POST /home/wall-plates$0.002Developer Utilities
Wall sheathing calculator
4x8 sheets from exterior wall area, free
POST /home/wall-sheathing-sheets$0.002Developer Utilities
Wallpaper paste calculator
paste from rolls and coverage per roll
POST /home/wallpaper-paste$0.002Developer Utilities
Water heater sizing calculator
tank from occupants and peak demand
POST /home/water-heater-sizing$0.002Developer Utilities
Wire ampacity calculator
safe current by gauge and insulation
POST /home/wire-ampacity-lookup$0.002Developer Utilities
Wire resistance run calculator
gauge, length & material
POST /home/wire-resistance-run$0.002Developer Utilities
Collatz sequence calculator
steps, peak and full hailstone path
POST /math/collatz$0.002Developer Utilities
GCD and LCM of multiple numbers free
POST /math/gcd-lcm$0.002Developer Utilities
Caballería area converter
free
POST /conv/caballeria-area$0.002Developer Utilities
Cantaro / kantar mass converter
free
POST /conv/cantaro-mass$0.002Developer Utilities
Chinese chi/cun length converter
free
POST /conv/chi-cun-length$0.002Developer Utilities
cmH₂O pressure converter
free
POST /conv/cmh2o-pressure$0.002Developer Utilities
Dirham (mass) converter
free
POST /conv/dirham-mass$0.002Developer Utilities
Fanegada area converter
free
POST /conv/fanegada-area$0.002Developer Utilities
Firkin (beer) volume converter
free
POST /conv/firkin-volume$0.002Developer Utilities
Geologic rate converter
free
POST /conv/geologic-rate$0.002Developer Utilities
Mithqal mass converter
free
POST /conv/mithqal-mass$0.002Developer Utilities
Newton temperature scale converter
free
POST /conv/newton-temperature$0.002Developer Utilities
Parasang / farsakh converter
free
POST /conv/parasang-length$0.002Developer Utilities
French toise length converter
free
POST /conv/toise-length$0.002Developer Utilities
ISO 8601 week number
week and week-year from any date
POST /date/week-number$0.002Developer Utilities
Fixture unit demand calculator
peak water GPM from FU
POST /home/fixture-unit-demand$0.002Developer Utilities
Lawn mowing area calculator
area, passes, and mowing time
POST /home/lawn-mowing-area$0.002Developer Utilities
Overseeding calculator
seed pounds from lawn area and rate per 1000 ft²
POST /home/overseeding$0.002Developer Utilities
PEX tubing calculator
total length from fixtures and average run
POST /home/pex-tubing$0.002Developer Utilities
Pipe water weight calculator
water mass in a filled pipe for hangers
POST /home/pipe-water-weight$0.002Developer Utilities
Play sand calculator
bags and tons for a sandbox by size and depth
POST /home/play-sand$0.002Developer Utilities
Raised bed soil calculator
fill volume from length, width and height free
POST /home/raised-bed-soil$0.002Developer Utilities
Septic tank sizing calculator
capacity from bedrooms and occupants
POST /home/septic-tank-sizing$0.002Developer Utilities
Solar panel count calculator
panels from monthly kWh and sun hours
POST /home/solar-panel-count$0.002Developer Utilities
Sprinkler head count calculator
heads from lawn area and coverage
POST /home/sprinkler-head-count$0.002Developer Utilities
Subpanel feeder calculator
wire size & breaker from load and distance
POST /home/subpanel-feeder$0.002Developer Utilities
Toilet water usage calculator
daily & yearly gallons from GPF
POST /home/toilet-water-usage$0.002Developer Utilities
Transformer sizing calculator
kVA from load and voltage
POST /home/transformer-sizing$0.002Developer Utilities
Water service line calculator
size pipe from demand and street pressure
POST /home/water-service-line$0.002Developer Utilities
Calculate daily calorie needs from BMR and activity level
POST /calc2/calorie-needs-activity$0.002Developer Utilities
Calculate tip and split a bill
total and share per person
POST /calc2/tip-split-bill$0.002Developer Utilities
Calculate Recommended Daily Water Intake by Weight
POST /calc2/water-intake-recommend$0.002Developer Utilities
Calculate grade needed on final exam
required score calculator
POST /calc3/grade-needed-final-exam$0.002Developer Utilities
Generate an analogous color palette from any hex color
POST /color/analogous-palette$0.002Developer Utilities
Color Blindness Simulator for Protanopia, Deuteranopia, and Tritanopia
POST /color/blindness-simulate$0.002Developer Utilities
Convert CMYK to RGB
percentage to 0–255 values
POST /color/cmyk-to-rgb$0.002Developer Utilities
Compute WCAG color contrast ratio
AA and AAA results
POST /color/contrast-ratio-wcag$0.002Developer Utilities
Expand hex color shorthand
#RGB to #RRGGBB, free
POST /color/hex-shorthand-expand$0.002Developer Utilities
Convert hex color to RGB values from 0 to 255
POST /color/hex-to-rgb$0.002Developer Utilities
Convert HSL to RGB
get red, green and blue values 0–255
POST /color/hsl-to-rgb$0.002Developer Utilities
Perceived brightness calculator
classify an RGB color as light or dark
POST /color/luminance-perceived$0.002Developer Utilities
Material Design palette generator
create shades 50 to 900
POST /color/material-palette-generate$0.002Developer Utilities
Lookup color name from hex
find the closest CSS color
POST /color/name-lookup$0.002Developer Utilities
Estimate the nearest Pantone-style color family from RGB
POST /color/pantone-nearest-estimate$0.002Developer Utilities
Seeded random color palette generator
repeatable hex colors
POST /color/random-palette-seeded$0.002