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
Exterior angles of a triangle calculator
from the three interior angles
POST /math/exterior-angles-of-a-triangle$0.002Developer Utilities
Rent vs Buy Equipment Calculator
Compare Total Costs
POST /realestate/rent-vs-buy-equipment$0.002Developer Utilities
Most frequent value calculator
find modes and counts in a list
POST /stat/most-frequent-value$0.002Developer Utilities
Percent change between values calculator
increase or decrease
POST /stat/percent-change$0.002Developer Utilities
Total monthly subscriptions cost calculator
recurring spend free
POST /str/monthly-subscriptions-total$0.002Developer Utilities
Spell out dollar amount calculator
invoices & contracts, free
POST /str/spell-dollar-amount$0.002Developer Utilities
Overnight layover cost calculator
compare with a direct flight
POST /travel/overnight-layover-cost$0.002Developer Utilities
Bishop Score Calculator
Cervical Readiness Assessment
POST /health/bishop-score$0.002Developer Utilities
Pediatric BMI z-score calculator
LMS method from L, M, S
POST /health/bmi-z-pediatric$0.002Developer Utilities
Corrected reticulocyte count calculator
retic% × Hct / normal Hct
POST /health/corrected-reticulocyte$0.002Developer Utilities
Creatinine clearance calculator
Cockcroft-Gault CrCl free
POST /health/creatinine-clearance$0.002Developer Utilities
Due date from CRL ultrasound calculator
gestational age free
POST /health/due-date-crl$0.002Developer Utilities
FIB-4 liver fibrosis calculator
age, AST, ALT and platelets
POST /health/fib4$0.002Developer Utilities
HOMA-IR insulin resistance calculator
fasting glucose and insulin
POST /health/homa-ir$0.002Developer Utilities
IVF transfer due date calculator
embryo age to estimated delivery date
POST /health/ivf-due-date$0.002Developer Utilities
Optimal nap length calculator
find your nap end time
POST /health/nap-length$0.002Developer Utilities
QTc Framingham Calculator
Correct QT for Heart Rate
POST /health/qtc-framingham$0.002Developer Utilities
Wake time after sleep cycles calculator
POST /health/wake-after-cycles$0.002Developer Utilities
Pregnancy weeks to months converter
four-week months
POST /health/weeks-to-months-preg$0.002Developer Utilities
Brick wall calculator
estimate bricks and mortar joints
POST /home/brick-wall$0.002Developer Utilities
Ceiling joist count calculator
joists from room length and OC spacing
POST /home/ceiling-joist-count$0.002Developer Utilities
Collar tie count calculator
ties from ridge length and required spacing
POST /home/collar-tie-count$0.002Developer Utilities
Concrete bag calculator
40, 60, or 80 lb bags from volume
POST /home/concrete-bags$0.002Developer Utilities
Concrete pier calculator
cylindrical pier and tube form volume
POST /home/concrete-pier$0.002Developer Utilities
Corner stud count calculator
extra studs for corners and tees
POST /home/corner-studs$0.002Developer Utilities
Deck footing count calculator
estimate posts and concrete footings
POST /home/deck-footing-count$0.002Developer Utilities
Drip Edge Calculator
Linear Feet and 10-Foot Pieces
POST /home/drip-edge$0.002Developer Utilities
Footing concrete volume calculator
strip footing L×W×D and bags, free
POST /home/footing-volume$0.002Developer Utilities
Gutter Flow Capacity Calculator
Size Gutters for Roof Runoff
POST /home/gutter-capacity$0.002Developer Utilities
Gutter hanger calculator
hangers from length and spacing, free
POST /home/gutter-hangers$0.002Developer Utilities
Joist hanger count calculator
hangers from joists and bearing ends
POST /home/joist-hanger-count$0.002Developer Utilities
Lumber Weight Calculator
Board Feet to Pounds and Kilograms
POST /home/lumber-weight$0.002Developer Utilities
Rebar Grid Calculator
Count Bars and Total Length
POST /home/rebar-grid$0.002Developer Utilities
Roof rainwater runoff calculator
peak volume from area and rainfall depth
POST /home/roof-rain-runoff$0.002Developer Utilities
Roof sheathing calculator
4x8 plywood or OSB sheets
POST /home/roof-sheathing-sheets$0.002Developer Utilities
Roofing Squares Calculator
Include Pitch and Waste
POST /home/roofing-squares$0.002Developer Utilities
Shingle bundle calculator
squares to bundles with waste free
POST /home/shingle-bundles$0.002Developer Utilities
Stair stringer notch layout
riser and tread marks from rise and run
POST /home/stair-stringer-notch$0.002Developer Utilities
Stone Veneer Calculator
Estimate Flat Stone and Corner Pieces
POST /home/stone-veneer$0.002Developer Utilities
Valley rafter length calculator
run, pitch, diagonal factor
POST /home/valley-rafter-length$0.002Developer Utilities
Aggregate tonnage calculator
volume to tons for gravel, sand, stone
POST /home/aggregate-tonnage$0.002Developer Utilities
Concrete cost estimator
volume × price/yd³ + short-load fee
POST /home/concrete-cost$0.002Developer Utilities
Corner bead calculator
linear feet for metal or paper bead
POST /home/corner-bead$0.002Developer Utilities
Door paint calculator
estimate paint for one or both sides
POST /home/door-paint$0.002Developer Utilities
Polymeric sand calculator
estimate bags for paver joints
POST /home/polymeric-sand$0.002Developer Utilities
Primer calculator
estimate gallons for walls or ceilings
POST /home/primer-paint$0.002Developer Utilities
Tile edge trim calculator
linear feet of bullnose or edging
POST /home/tile-edge-trim$0.002Developer Utilities
Fourth root calculator
principal ∜x of any non-negative number, free
POST /math/fourth-root$0.002Developer Utilities
Tile backer board calculator
cement board sheets from area and waste
POST /home/backer-board$0.002Developer Utilities
Dehumidifier sizing calculator
estimate pints per day
POST /home/dehumidifier-sizing$0.002Developer Utilities
Epoxy floor coating calculator
kits from floor area and kit coverage
POST /home/epoxy-floor$0.002Developer Utilities
Flooring underlayment calculator
foam or cork rolls by area
POST /home/floor-underlayment$0.002Developer Utilities
Furnace sizing calculator
BTU from square footage and climate
POST /home/furnace-sizing$0.002Developer Utilities
Insulation batt calculator
bundles for walls or attics
POST /home/insulation-batts$0.002Developer Utilities
Insulation cost estimator
material cost from area, R-value and price/sqft
POST /home/insulation-cost$0.002Developer Utilities
Peel-and-stick wallpaper calculator
rolls by area and pattern waste
POST /home/peel-stick-wallpaper$0.002Developer Utilities
Recommended R-value calculator
attic, wall & floor by climate zone
POST /home/recommended-r-value$0.002Developer Utilities
Room CFM calculator
airflow from room volume and ACH
POST /home/room-cfm$0.002Developer Utilities
Window casing calculator
linear feet of trim
POST /home/window-casing$0.002Developer Utilities
Fractional exponent calculator
base^(numerator/denominator)
POST /math/fractional-exponent$0.002