Chemistry, Physics, DIY, Math, Photography, Music, Developer utilities — all 100% free, client-side, no signup needed.
Calculate molar mass from chemical formula
ChemistryFind mole ratios from balanced equations
ChemistrypH from strong acid concentration
ChemistrypH from Ka and concentration
ChemistrypH from strong base concentration
ChemistrypH from Kb and concentration
ChemistrySolve PV=nRT for any variable
ChemistryP1V1/T1 = P2V2/T2 solver
ChemistryP1V1 = P2V2 at constant temperature
ChemistryV1/T1 = V2/T2 at constant pressure
ChemistryFind the limiting reactant in a reaction
ChemistryCalculate reaction percent yield
ChemistryCalculate moles per liter of solution
ChemistryCalculate moles per kg of solvent
ChemistryM1V1=M2V2 dilution problems
ChemistrypH of buffer solutions
ChemistrypH = pKa + log([A⁻]/[HA])
ChemistrySolubility product constant
ChemistryFind oxidation states in compounds
ChemistryBalance chemical equations automatically
ChemistryEmpirical formula from % composition
ChemistryMolecular formula from empirical + mass
Chemistry% mass of each element in a compound
ChemistryΔHrxn from formation enthalpies
ChemistryΔG = ΔH - TΔS
ChemistrySolve for v, a, t, d with 3 known values
PhysicsRange, height, and time of flight
PhysicsTime and velocity of falling objects
PhysicsForce for circular motion
Physicsτ = F × r × sin(θ)
PhysicsI for rod, disk, sphere and more shapes
PhysicsKE = ½Iω² for rotating bodies
PhysicsL = Iω for rotational systems
PhysicsW = F·d·cos(θ)
PhysicsKE = ½mv²
PhysicsPE = mgh
PhysicsF = -kx (Hooke's Law)
Physicsv = f × λ
PhysicsdB = 10·log(I/I₀)
PhysicsSolve V=IR for any variable
PhysicsTotal resistance in series circuits
PhysicsTotal resistance in parallel circuits
PhysicsC = εA/d for parallel plate capacitors
PhysicsF = qvB for charged particles
PhysicsBoards needed for any deck size
DIY & HomePosts and panels for fencing
DIY & HomeCubic feet/yards of concrete needed
DIY & HomeConcrete for cylindrical footings
DIY & HomeGallons of paint for any room
DIY & HomeFloor tiles needed with waste factor
DIY & HomeShingle bundles for your roof area
DIY & HomeSiding panels for exterior walls
DIY & HomeDrywall sheets needed for any area
DIY & HomeBoxes of flooring with waste %
DIY & HomeStuds needed for any wall length
DIY & HomeOptimal joist spacing for your span
DIY & HomeRequired beam size for span and load
DIY & HomeCubic feet of soil for raised beds
DIY & HomeCubic yards of mulch needed
DIY & HomePavers needed for any patio area
DIY & HomeBricks needed for walls
DIY & HomeGrout bags needed for tile jobs
DIY & HomeGallons of stain for wood surfaces
DIY & HomeX% of Y, percentage change, difference
MathAdd, subtract, multiply & divide fractions
MathPrime factors, divisors, factor tree
MathLeast common multiple & greatest divisor
MathSolve ax² + bx + c = 0 with steps
MathBinary, octal, decimal, hex conversion
MathMean, median, mode, standard deviation
MathSimplify ratios and solve proportions
MathConvert and operate in scientific notation
MathFind any side of a right triangle
MathArea and perimeter for any shape
MathPowers, roots, and logarithms
MathNear/far limits of sharp focus
PhotographyMaximum sharpness from near to infinity
PhotographyShutter speed from ISO and aperture
PhotographyFocal length from subject size & distance
PhotographyEstimated noise level from ISO
Photographyf-number from pupil diameter
PhotographyMagnification ratio for macro photography
PhotographyCoC for depth of field calculations
PhotographyLong exposure time with ND filters
PhotographySunrise and golden hour times by location
PhotographyFull/half/third-stop shutter speed scale
PhotographyConvert between formats and sensor sizes
PhotographyIdentify chord from its notes
MusicNotes for any scale and root
MusicSong length from BPM and beat count
MusicName the interval between two notes
MusicPractice with a gradual tempo increase
MusicConvert Hz to musical note
MusicConvert musical note to Hz
MusicFrequencies for different temperaments
MusicValidate and pretty-print JSON
DeveloperEncode or decode Base64 strings
DeveloperTest regex patterns with explanations
DeveloperConvert hex colors to RGB and back
DeveloperFormat and indent SQL queries
DeveloperEncode or decode URL strings
DeveloperMinify CSS to reduce file size
DeveloperEncode/decode HTML special characters
DeveloperRemove duplicate lines from any text list
Text Processingsnake_case, camelCase, kebab-case…
Text ProcessingWord/character count + reading time
Text ProcessingCompare two texts and highlight differences
Text ProcessingRemove extra spaces and clean up text
Text ProcessingReverse characters, words or lines
Text ProcessingGenerate placeholder text for mockups
Text ProcessingSecure passwords + memorable passphrases
Data GeneratorsGenerate single or bulk UUIDs
Data GeneratorsRandom integers, dice rolls, coin flips
Data GeneratorsMD5, SHA-1, SHA-256, SHA-512 from text
Data GeneratorsBeautiful color palettes for web design
Data GeneratorsExact age in years, months, days + birthday
Time & ScheduleCountdown and stopwatch with audio alerts
Time & ScheduleDays, weeks, months between any two dates
Time & ScheduleConvert time between any two time zones
Time & ScheduleConvert timestamps to dates and vice versa
Time & ScheduleScale any recipe to any number of servings
Baking & CookingIngredient substitutes when you're missing one
Baking & CookingConvert between dry, instant & fresh yeast
Baking & CookingBaker's percentage and dough hydration
Baking & CookingFind pan substitutions by volume
Baking & CookingCalculate molar mass from chemical formula
Find mole ratios from balanced equations
pH from strong acid concentration
pH from Ka and concentration
pH from strong base concentration
pH from Kb and concentration
Solve PV=nRT for any variable
P1V1/T1 = P2V2/T2 solver
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Every tool works perfectly on phones, tablets and desktops.
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