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
Associative property of addition
grouped sums, free
POST /math/associative-property$0.002
Developer Utilities
Area of a quadrilateral
shoelace from four vertices
POST /math/area-quadrilateral$0.002
Developer Utilities
Average percentage calculator
mean of a list of percentages
POST /math/average-percentage$0.002
Developer Utilities
Average calculator
arithmetic mean of a list of numbers
POST /math/average$0.002
Developer Utilities
Base of a triangle calculator
find base from area and height
POST /math/base-of-a-triangle$0.002
Developer Utilities
Bessel function calculator
J_n(x) first kind, free
POST /math/bessel-function$0.002
Developer Utilities
Convert fraction to percentage
turn a/b into a percent, free
POST /math/convert-fraction-to-percentage$0.002
Developer Utilities
Crescent area calculator
two radii and center distance, free
POST /math/crescent-area$0.002
Developer Utilities
Pipe cross-sectional area
A = πd²/4 from inner diameter
POST /math/cross-sectional-area$0.002
Developer Utilities
Csc calculator
cosecant of an angle in degrees or radians
POST /math/csc$0.002
Developer Utilities
Dividing radicals calculator
simplify and rationalize the quotient
POST /math/dividing-radicals$0.002
Developer Utilities
Distributive property calculator
expand a(b + c), free
POST /math/distributive-property-old$0.002
Developer Utilities
Divide complex numbers
(a+bi)/(c+di) real and imag, free
POST /math/divide-complex-numbers$0.002
Developer Utilities
Exponential notation converter
decimal ↔ a×10^n, free
POST /math/exponential-notation$0.002
Developer Utilities
Factor calculator
all factors of a positive integer
POST /math/factor$0.002
Developer Utilities
Factoring trinomials calculator
ax²+bx+c into two binomials
POST /math/factoring-trinomials$0.002
Developer Utilities
Fifth root calculator
real fifth root of any finite number, free
POST /math/fifth-root$0.002
Developer Utilities
Fermat's little theorem calculator
a^(p−1) mod p residue
POST /math/fermats-little-theorem$0.002
Developer Utilities
Greatest common divisor
Euclidean GCD of two integers
POST /math/greatest-common-divisor$0.002
Developer Utilities
Half-angle formula
sin, cos, tan of θ/2 in degrees
POST /math/half-angle$0.002
Developer Utilities
Greatest common factor calculator
GCF of a list of integers
POST /math/greatest-common-factor$0.002
Developer Utilities
Hexagon calculator
regular hexagon area and perimeter
POST /math/hexagon$0.002
Developer Utilities
Inverse modulo calculator
multiplicative inverse a⁻¹ mod m
POST /math/inverse-modulo$0.002
Developer Utilities
Isosceles trapezoid area
two bases and height
POST /math/isosceles-trapezoid-area$0.002
Developer Utilities
LCD calculator
least common multiple of integers
POST /math/lcd$0.002
Developer Utilities
LCM calculator
least common multiple of integers, free
POST /math/lcm$0.002
Developer Utilities
Least to greatest fractions
sort a list from smallest to largest
POST /math/least-to-greatest-fractions$0.002
Developer Utilities
Length of a rectangle calculator
from area and width, free
POST /math/length-of-a-rectangle$0.002
Developer Utilities
Linear combination calculator
weighted sum of vectors
POST /math/linear-combination$0.002
Developer Utilities
Linear-feedback shift register
LFSR bit sequence from taps
POST /math/linear-feedback-shift-register$0.002
Developer Utilities
Line of intersection of two planes
parametric form
POST /math/line-of-intersection-of-two-planes$0.002
Developer Utilities
Log2 calculator
base-2 logarithm of a positive number
POST /math/log-2$0.002
Developer Utilities
Mean calculator
arithmetic mean of a list of numbers
POST /math/mean$0.002
Developer Utilities
Long multiplication calculator
digit-by-digit product, free
POST /math/long-multiplication$0.002
Developer Utilities
Möbius strip calculator
surface area and edge length
POST /math/mobius-strip$0.002
Developer Utilities
Multiply complex numbers
(a+bi)(c+di) product, free
POST /math/multiply-complex-numbers$0.002
Developer Utilities
Logical NOR calculator
true only when both inputs are false
POST /math/nor$0.002
Developer Utilities
Null space calculator
kernel basis of a matrix from its rows
POST /math/null-space$0.002