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Every physics formula you need, solved in your pocket
PhysRef is a complete physics formula reference for students, engineers, and science enthusiasts — hundreds of formulas, physical constants, and built-in calculators that work entirely without internet.
Mechanics · Kinematics
v = v₀ + at
- v
- final velocity (m/s)
- v₀
- initial velocity (m/s)
- a
- acceleration (m/s²)
- t
- time (s)
Illustration — every PhysRef formula includes variable definitions and units.
Formula sheets scatter. Wi-Fi drops. Exams don't wait.
Studying physics the hard way
You're mid-problem-set and can't remember whether that kinematics equation uses ½at² or at². The formula sheet is a crumpled PDF, the website you bookmarked needs Wi-Fi, and half the "free" formula apps interrupt you with ads.
Worse, a bare equation doesn't tell you what each symbol means, which units to use, or where the formula comes from — so you memorize without understanding.
The PhysRef way
PhysRef bundles hundreds of formulas — each with variable definitions, units, and related concepts — plus physical constants, calculators, and a unit converter into one app that never needs a connection.
Search by formula name, variable, or concept. Read the step-by-step derivation. Enter your known values and let the built-in calculator compute the unknown. Add your own notes for exam day.
A full physics toolkit, not just a formula list
Everything below is bundled in the app and works completely offline.
Comprehensive formula database
Hundreds of formulas organized by topic. Each one includes variable definitions, units, and related concepts — with bookmarks for quick access.
Built-in calculators
Stop doing manual algebra. Enter your known values and instantly compute the unknown variable, with input validation and results in appropriate units.
Physical constants table
Speed of light, gravitational constant, Planck's constant, electron mass, Boltzmann constant, and dozens more — all using standard reference data.
Unit converter — 14 categories
Length, mass, time, velocity, acceleration, force, energy, power, pressure, temperature, electric charge, electric current, angle, and frequency.
Personal notes & bookmarks
Attach your own notes to any formula — problem-solving strategies, exam reminders, or flags on the formulas you find tricky.
Step-by-step derivations
Understand where formulas come from. Derivations connect fundamental principles to the equations you actually use, so you learn instead of just memorizing.
From first-semester mechanics to modern physics
Formulas are organized by topic, and the content covers AP Physics 1, AP Physics 2, AP Physics C, IB Physics, and introductory university physics courses.
- Mechanics
- Thermodynamics
- Waves
- Electricity & Magnetism
- Optics
- Modern Physics
Built for the way physics students actually study
Find it fast
Search by formula name, variable, or concept — or browse by topic. Bookmarks and search history keep your most-used formulas one tap away.
Understand it
Variable definitions, units, related formulas, and step-by-step derivations turn a bare equation into something you can reason about on exam day.
Solve with it
Use the built-in calculators to compute unknowns from your known values, check units with the converter, and record your strategy as a personal note.
Questions students ask before downloading
Yes. PhysRef is free on the App Store, with no ads. There is no account to create and no sign-up required.
Yes — 100% offline. All formulas, constants, calculators, and the unit converter are bundled inside the app, so it works on airplanes, in basements, or anywhere without signal.
Formulas are organized by topic: Mechanics, Thermodynamics, Waves, Electricity and Magnetism, Optics, and Modern Physics. Each formula includes variable definitions, units, and related concepts.
Yes. PhysRef covers content from AP Physics 1, AP Physics 2, AP Physics C, IB Physics, and introductory university physics courses — for exam prep and homework alike.
No. Your data stays on your device. PhysRef does not collect personal information — no tracking, no analytics, and no ads.
It calculates. Built-in calculators let you enter known values and instantly compute the unknown variable, with input validation and results shown in appropriate units. There is also a unit converter covering 14 categories.
PhysRef is a universal iOS app for iPhone and iPad, requiring iOS 15.1 or later. It supports dark and light themes and is localized in 20+ languages.
Free physics study guides
Evergreen, exam-ready explainers written to accompany PhysRef.
How to Memorize Physics Formulas (Without Just Cramming)
Retrieval practice, derivation-first learning, and other techniques that make formulas stick past the exam.
Read the guide →The AP Physics Formula Sheet: What It Gives You — and What It Doesn't
How to use the official equation sheet strategically, and how to prepare for everything it leaves out.
Read the guide →Unit Conversions in Physics: SI Units, Prefixes, and Dimensional Analysis
A practical system for never losing points to unit errors again.
Read the guide →Physical Constants Explained: c, G, h, k and Friends
What the fundamental constants mean, where their values come from, and when you need them.
Read the guide →Put the whole formula book in your pocket
Free, ad-free, and fully offline. Built for physics students who want a reliable reference that works anywhere.