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
Ohm's law calculator
V I R P free online
POST /dev/ohm-law$0.002
Developer Utilities
One rep max calculator
Epley Brzycki free
POST /dev/one-rep-max$0.002
Developer Utilities
Profit margin calculator
free online
POST /dev/profit-margin$0.002
Developer Utilities
Simple interest calculator
free online
POST /dev/simple-interest$0.002
Developer Utilities
Download time calculator
free online
POST /dev/download-time$0.002
Developer Utilities
Discount calculator
percent off and final price free in your browser
POST /dev/discount-calculator$0.002
Developer Utilities
Time calculator
hours, minutes and seconds free in your browser
POST /dev/time-calculator$0.002
Developer Utilities
Body fat calculator
US Navy free
POST /dev/body-fat$0.002
Developer Utilities
Break even calculator
free online
POST /dev/break-even$0.002
Developer Utilities
Cat age calculator
free online
POST /dev/cat-age$0.002
Developer Utilities
Dog age calculator
free online
POST /dev/dog-age$0.002
Developer Utilities
Due date calculator
free online
POST /dev/due-date$0.002
Developer Utilities
GPA calculator
free online
POST /dev/gpa-calculator$0.002
Developer Utilities
Heart rate zones
Karvonen free online
POST /dev/heart-rate-zones$0.002
Developer Utilities
Ideal weight calculator
free online
POST /dev/ideal-weight$0.002
Developer Utilities
Ovulation calculator
free online
POST /dev/ovulation-calculator$0.002
Developer Utilities
Speed distance time calculator
free
POST /dev/speed-distance-time$0.002
Developer Utilities
Water intake calculator
free online
POST /dev/water-intake$0.002
Developer Utilities
Fuel cost calculator
trip cost free in your browser
POST /dev/fuel-cost$0.002
Developer Utilities
chmod calculator
rwx to octal free in your browser
POST /dev/chmod-calculator$0.002
Developer Utilities
Quadratic equation solver
roots free in your browser
POST /dev/quadratic-equation$0.002
Developer Utilities
Pythagorean theorem calculator
free in your browser
POST /dev/pythagoras$0.002
Developer Utilities
EV charge time calculator
free online
POST /dev/ev-charge-time$0.002
Developer Utilities
Inflation calculator
free online
POST /dev/inflation-calculator$0.002
Developer Utilities
A1C converter
educational ADA free
POST /dev/a1c-converter$0.002
Developer Utilities
BAC calculator
educational estimate, free online
POST /dev/bac-calculator$0.002
Developer Utilities
Dew point calculator
free online
POST /dev/dew-point$0.002
Developer Utilities
Heat index calculator
NWS free online
POST /dev/heat-index$0.002
Developer Utilities
Macro calculator
protein carbs fat free
POST /dev/macro-calculator$0.002
Developer Utilities
Moon phase calculator
free online
POST /dev/moon-phase$0.002
Developer Utilities
Plate calculator
barbell loading free
POST /dev/plate-calculator$0.002
Developer Utilities
Tire size calculator
diameter free online
POST /dev/tire-size$0.002
Developer Utilities
Permutation & combination calculator
free in your browser
POST /dev/permutation-combination$0.002
Developer Utilities
Resistor color code calculator
free in your browser
POST /dev/resistor-color-code$0.002
Developer Utilities
ROI calculator
return on investment free in your browser
POST /dev/roi$0.002
Developer Utilities
Bell number calculator
free
POST /math/bell-number$0.002
Developer Utilities
Equilateral triangle calculator
free
POST /math/equilateral-triangle$0.002
Developer Utilities
Euler triangle OI distance calculator
free
POST /math/euler-triangle-formula$0.002
Developer Utilities
Intersecting chords calculator
free
POST /math/intersecting-chords$0.002
Developer Utilities
Jacobsthal number calculator
free
POST /math/jacobsthal-number$0.002
Developer Utilities
Oblique cylinder calculator
free online
POST /math/oblique-cylinder$0.002
Developer Utilities
Spherical excess calculator
Girard free
POST /math/spherical-excess$0.002
Developer Utilities
Subfactorial calculator
free
POST /math/subfactorial$0.002
Developer Utilities
Torus sector calculator
free
POST /math/torus-sector$0.002
Developer Utilities
Tribonacci number calculator
free
POST /math/tribonacci-number$0.002
Developer Utilities
Trirectangular tetrahedron calculator
free
POST /math/trirectangular-tetrahedron$0.002
Developer Utilities
Break even occupancy calculator
free
POST /finance/break-even-occupancy$0.002
Developer Utilities
Capital gains tax estimator
free
POST /finance/capital-gains-tax$0.002
Developer Utilities
DSCR calculator
free
POST /finance/debt-service-coverage$0.002
Developer Utilities
FHA MIP calculator
free
POST /finance/fha-mip$0.002
Developer Utilities
FIRE number calculator
free
POST /finance/fire-number$0.002
Developer Utilities
Hard money loan calculator
free
POST /finance/hard-money-loan$0.002
Developer Utilities
Interest capitalization calculator
free
POST /finance/interest-capitalization$0.002
Developer Utilities
Mortgage recast calculator
free
POST /finance/mortgage-recast$0.002
Developer Utilities
One percent rule calculator
free
POST /finance/one-percent-rule$0.002
Developer Utilities
Rule of 78 rebate calculator
free
POST /finance/rule-of-78-rebate$0.002
Developer Utilities
SS claim breakeven calculator
free
POST /finance/ss-claim-breakeven$0.002
Developer Utilities
French Republican calendar
free
POST /date/french-republican$0.002
Developer Utilities
Interval intersection
free
POST /date/interval-intersection$0.002
Developer Utilities
Juche era converter
free
POST /date/juche$0.002