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
Circle theorems calculator
inscribed, central and related angles
POST /math/circle-theorems$0.002Developer Utilities
Circumcenter of a triangle
center of the circumscribed circle
POST /math/circumcenter-of-a-triangle$0.002Developer Utilities
Force for constant speed calculator
F = μ·W on a rough floor
POST /mech/force-constant-speed-friction$0.002Developer Utilities
Period of circular motion calculator
T = 2πr/v free online
POST /mech/period-circular-motion$0.002Developer Utilities
Time to slide down incline calculator
rough plane, free
POST /mech/time-slide-down-incline$0.002Developer Utilities
Convert text to the NATO phonetic alphabet
Alpha, Bravo, Charlie
POST /enc/nato-phonetic-convert$0.002Developer Utilities
Circumference calculator
from the diameter, free online
POST /math/circumference$0.002Developer Utilities
RPM to angular frequency calculator
ω = 2π·(rpm/60) in rad/s
POST /mech/angular-frequency-from-rpm$0.002Developer Utilities
Conical pendulum calculator
period and speed from length and angle
POST /mech/conical-pendulum$0.002Developer Utilities
Tangential acceleration calculator
a_t = α·r free online
POST /mech/tangential-acceleration$0.002Developer Utilities
Seeded numeric PIN generator
reproducible PINs with pattern checks
POST /security/password-pin-seeded$0.002Developer Utilities
Generate an acrostic poem skeleton from any word
POST /str/acrostic-generate$0.002Developer Utilities
Circumference to diameter
diameter from circumference online
POST /math/circumference-to-diameter$0.002Developer Utilities
Conservation of energy calculator
speed from height change
POST /mech/conservation-mechanical-energy$0.002Developer Utilities
Change in potential energy calculator
ΔPE = m·g·Δh in joules, free
POST /mech/gravitational-pe-change$0.002Developer Utilities
Circumference and area of a circle
2·π·r and π·r² from the radius
POST /math/circumference-area-circle$0.002Developer Utilities
Circumference to Radius Calculator
Free Online
POST /math/circumference-to-radius$0.002Developer Utilities
Circumscribed circle
center and radius of the circle through three points
POST /math/circumscribed-circle$0.002Developer Utilities
Classifying triangles by sides and angles
free
POST /math/classifying-triangles$0.002Developer Utilities
Clock angle calculator
degrees between the hour and minute hands
POST /math/clock-angle$0.002Developer Utilities
Impact force calculator
average force from KE and stopping distance
POST /mech/impact-force-stopping-distance$0.002Developer Utilities
Power to lift load calculator
watts from mass, height and time (P=mgh/t)
POST /mech/power-to-lift$0.002Developer Utilities
Work to raise a mass calculator
W = m·g·h in joules, free
POST /mech/work-against-gravity$0.002Developer Utilities
Brand palette usage ratio checker
compare color coverage
POST /date/brand-color-usage-ratio-check$0.002Developer Utilities
Cofactor expansion calculator
det(A) along any row or column, free
POST /math/cofactor-expansion-old$0.002Developer Utilities
Cofactor matrix calculator
every cofactor C(i,j) of a square matrix
POST /math/cofactor-matrix$0.002Developer Utilities
Cofunction calculator
sin cos tan cot sec csc via the complementary angle
POST /math/cofunction$0.002Developer Utilities
Climbing power calculator
watts from body weight, vertical gain & time
POST /mech/climbing-power$0.002Developer Utilities
Input power required calculator
P_in = P_out / η
POST /mech/input-power-required$0.002Developer Utilities
Kinetic energy lost in collision calculator
perfectly inelastic ΔKE
POST /mech/kinetic-energy-lost-collision$0.002Developer Utilities
Sprint burndown calculator
required daily velocity
POST /biz/burndown-remaining-estimate$0.002Developer Utilities
Calculate OKR key result progress percentage
POST /biz/okr-progress-percent$0.002Developer Utilities
Team sprint capacity calculator
focus factor and story points
POST /biz/team-capacity-planning$0.002Developer Utilities
Calculate agile team average velocity and planning velocity
POST /date/velocity-average-calculate$0.002Developer Utilities
Coin rotation paradox
rotations of a circle rolling around another, free
POST /math/coin-rotation-paradox$0.002Developer Utilities
Column space calculator
basis from pivot columns, free
POST /math/column-space$0.002Developer Utilities
Center of mass velocity calculator
v_cm from masses and velocities
POST /mech/center-of-mass-velocity$0.002Developer Utilities
Coefficient of restitution calculator
e = v_sep / v_app
POST /mech/coefficient-of-restitution$0.002Developer Utilities
Rocket thrust calculator
F = ṁ·v_e in newtons free
POST /mech/rocket-thrust$0.002Developer Utilities
Customer Account Health Score Calculator
Weighted Composite
POST /biz/customer-health-score-calc$0.002Developer Utilities
KPI gap to target calculator
absolute and percentage remaining
POST /biz/kpi-target-gap-calc$0.002Developer Utilities
Estimate contract renewal risk category from customer health
POST /biz/renewal-probability-estimate$0.002Developer Utilities
Least common denominator calculator
LCD of two fractions
POST /math/common-denominator$0.002Developer Utilities
Common factor calculator
shared factors of two or more integers, sorted
POST /math/common-factor$0.002Developer Utilities
Final angular velocity calculator
ω = ω₀ + αt, free
POST /mech/angular-velocity-final$0.002Developer Utilities
Impulse from force graph calculator
triangular force-time pulse area
POST /mech/impulse-from-force-graph$0.002Developer Utilities
Two-dimensional collision calculator
2D inelastic common velocity, free
POST /mech/two-body-collision-2d$0.002Developer Utilities
Leftover food safety window
USDA-style use-by dates by category, free
POST /life/leftover-food-safety-window$0.002Developer Utilities
Convert oven temperature scale
Celsius, Fahrenheit and gas mark
POST /life/oven-temp-convert$0.002Developer Utilities
Travel packing list generator
a checklist scaled to your trip
POST /life/packing-list-generate$0.002Developer Utilities
Complementary room color scheme
wall, trim and accent from one hex
POST /life/paint-color-room-match$0.002Developer Utilities
Pet food portion calculator
daily grams and cups for dogs or cats
POST /life/pet-food-portion$0.002Developer Utilities
Houseplant watering schedule calculator by pot size
POST /life/plant-watering-schedule$0.002Developer Utilities
Scale Recipe Ingredient Quantities by Serving Count
POST /life/recipe-scale-servings$0.002Developer Utilities
Convert recipe cooking units
cup, tbsp, tsp, ml, g, oz free
POST /life/recipe-unit-convert$0.002Developer Utilities
Least common multiple calculator
LCM of two integers, free online
POST /math/common-multiple$0.002Developer Utilities
Newborn feeding schedule calculator
feeds and volume by age
POST /life/baby-feeding-schedule$0.002Developer Utilities
Baby growth percentile lookup
estimate weight or height band
POST /life/baby-growth-percentile$0.002Developer Utilities
Split household chores schedule
fair weekly roommate rotation free
POST /life/chore-split-roommates$0.002Developer Utilities
Flashcard spaced repetition calculator
next review date
POST /life/flashcard-spaced-repetition$0.002