Statistics · Chemistry · Physics · Biology · Math
Precision instruments for statistics, science, and quantitative work.
Clean, ad-free calculators, explainers, and interactive tools for statistics, science, and quantitative work. Every one shows the method it runs and states its assumptions, so you can check the answer, not just take it.
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Jump straight to an instrument
Each one opens instantly, names the method it runs, and states its assumptions.
Activation Energy Calculator: Arrhenius Ea From Two Points or a Plot
Activation energy from two rate constants, one point, or an Arrhenius plot.
Hess's Law Calculator: Sum Steps or Formation Enthalpies
Reaction enthalpy by summing steps, or subtracting standard formation enthalpies.
Specific Heat Calculator: Solve for Any Variable
Solve q = mcΔT for heat, mass, specific heat, or temperature change.
Pressure Unit Converter
Convert a pressure across eleven units at once, with exact NIST factors.
Projectile Motion Calculator: Range, Height, and Trajectory Plot
Range, maximum height, and time of flight for 2D projectile motion, plotted.
Frequency to Wavelength Calculator: Exact Speed of Light
Frequency to wavelength with the exact speed of light, plus photon energy.
A/B Test Calculator
Compare two conversion rates or two means with a named frequentist test, effect size, and confidence interval.
Power and Sample Size Calculator
Plan sample size, power, or effect size for two proportions or two independent means.
Seven subjects
Browse by subject
Statistics, chemistry, physics, biology, math, notation, and academic writing. Each subject is its own set of instruments, with more added over time.
Statistics
30 toolsSignificance and A/B testing, power and sample size, confidence intervals, effect sizes, and a chooser that routes you to the right test.
Chemistry
12 toolsEquation balancing, stoichiometry, molar mass, solutions and dilutions, pH, and the gas laws.
Physics
11 toolsKinematics, circuits, optics, radioactive decay, and spectroscopy.
Biology
3 toolsGenetics and sequence tools: Punnett squares, Hardy-Weinberg, codon translation, and GC content.
Math
8 toolsSignificant figures, scientific notation, dimensional analysis, and printable graph paper.
Notation
3 toolsPlain-English decoders for math, statistics, and science symbols, plus a copy-paste symbol keyboard.
Academic writing
5 toolsCitation formatting, APA results sentences, and printable study aids.
Built and maintained by Eigenstate Labs. Every instrument names the method it runs and states its assumptions. See our disclaimer and how we calculate.