All tools — Page 3
983 useful tools. Browse a category or search the full toolkit.
ULID Generator
Generate timestamp-prefixed ULIDs with 80 bits of browser-generated random data.
DeveloperSHA Hash Generator
Calculate SHA-256, SHA-384, or SHA-512 digests of exact UTF-8 text using Web Crypto.
DeveloperMD5 Hash Generator
Calculate the legacy MD5 digest of UTF-8 text for compatibility and checksum comparison.
DeveloperCRC32 and Adler32 Calculator
Calculate standard CRC-32/IEEE and Adler-32 checksums of UTF-8 text in one pass.
DeveloperHMAC Generator
Generate HMAC-SHA-256, SHA-384, or SHA-512 authentication codes from UTF-8 text and a key.
DeveloperSRI Hash Generator
Generate a Subresource Integrity SHA-2 token for exact pasted UTF-8 JavaScript or CSS contents.
DeveloperURL Parser
Inspect HTTP(S) URL components, normalized hostnames, and repeated query parameters without visiting a link.
DeveloperQuery String Converter
Convert URL query text to ordered JSON pairs, or serialize pairs while preserving duplicate names.
DeveloperNumber Base Converter
Convert signed integers between bases 2 through 36 using exact arbitrary-precision arithmetic.
ColorsColor Converter
Convert opaque sRGB colors between HEX, integer RGB, and HSL representations.
ColorsColor Contrast Checker
Calculate WCAG sRGB contrast and report AA/AAA text thresholds for two opaque colors.
ColorsCSS Gradient Generator
Generate a two-color linear-gradient declaration with validated colors, angle, and stop positions.
DeveloperRobots.txt Generator
Build one crawler-rule group and optional sitemap lines with validated paths and URLs.
DeveloperCSP Policy Builder
Build a conservative Content-Security-Policy response header using exact HTTPS source origins.
MathPercentage Change Calculator
Measure an increase or decrease relative to an original value, with the signed difference shown.
MathPercentage Points Calculator
Compare two percentage rates using both percentage-point difference and relative percentage change.
MathRatio Calculator
Simplify a whole-number ratio and see each part as a share of the combined total.
MathFraction Calculator
Add, subtract, multiply, or divide two fractions and reduce the exact result.
MathWeighted Average Calculator
Calculate an average from paired values and nonnegative weights without manually normalizing weights.
MathDescriptive Statistics Calculator
Summarize a numeric list with mean, median, modes, range, count, and sum.
MathStandard Deviation Calculator
Measure spread using sample or population variance and standard deviation for a numeric list.
MathGeometric Mean Calculator
Find the multiplicative average of positive observations using a logarithmic calculation.
MathHarmonic Mean Calculator
Average positive rates using the reciprocal-based harmonic mean.
MathRoot Mean Square Calculator
Calculate RMS magnitude for a list of signed or unsigned observations.
MathCombinations and Permutations Calculator
Count selections and ordered arrangements without repetition using exact integer arithmetic.
MathFactorial Calculator
Compute the exact factorial of a nonnegative whole number, including 0!.
MathBinomial Probability Calculator
Find exact-count and cumulative probabilities for independent trials with a fixed success chance.
MathZ-score Calculator
Standardize a value relative to a supplied mean and positive standard deviation.
MathPrime Number Checker
Determine primality for whole numbers up to 4,294,967,295 using bounded deterministic testing.
MathGCD and LCM Calculator
Find the greatest common divisor and least common multiple of a list of whole numbers.
MathScientific Notation Converter
Express a decimal or exponent-form number in scientific and engineering notation.
MathSignificant Figures Calculator
Round a numeric value to a chosen count of significant figures while retaining trailing zeros.
MathTriangle Calculator
Solve a triangle from three side lengths: area, perimeter, and all three angles.
MathCircle Calculator
Calculate circle area, circumference, and diameter from a positive radius.
MathRectangle Calculator
Find rectangle area, perimeter, diagonal, and aspect ratio from two side lengths.
MathCylinder Calculator
Calculate volume and total or lateral surface area for a right circular cylinder.
MathSphere Calculator
Find sphere volume, surface area, and diameter from its radius.
MathQuadratic Equation Solver
Solve ax² + bx + c = 0, including repeated and complex roots, with a stable real-root formula.
MathTwo-variable Linear System Solver
Solve two simultaneous linear equations ax + by = c and dx + ey = f.
MathLinear Regression Calculator
Fit a straight line to paired observations and report slope, intercept, and R².
CalculatorsROI Calculator
Calculate net gain and non-annualized return on investment from cost and total proceeds.
CalculatorsSimple Interest Calculator
Estimate interest earned or owed without compounding over a chosen number of years.
CalculatorsCompound Interest Calculator
Project a lump sum using a fixed nominal annual rate and selected compounding frequency.
CalculatorsLoan Amortization Calculator
Estimate a fixed monthly loan payment and download a complete principal-and-interest schedule.
CalculatorsSavings Goal Calculator
Estimate the monthly deposit required to reach a target balance by a fixed month count.
CalculatorsAnnualized Return Calculator
Calculate compound annual growth rate from a starting value, ending value, and elapsed years.
CalculatorsInflation Adjustment Calculator
Model future cost and unchanged-money purchasing power using your own constant inflation rate.
CalculatorsSales Tax and VAT Calculator
Add a user-entered tax rate to a net price or extract included tax from a gross price.