Stokes Law Calculator
Stokes' Law, Reynolds & Drag
$2.99 · Designed for iPad. Not verified for macOS.
Stokes' Law Calculator is the fastest, most accurate way to solve fluid dynamics problems on iPhone and iPad. Built for engineers, physicists, chemists, geologists, and students, it combines a polished scientific interface with a powerful calculation engine — and it works completely offline.
Solve Stokes' Drag Force, Terminal Velocity, and Reynolds Number in seconds. Pick which variable to solve for and the app rearranges the formula automatically: F = 6πμrv, Vt = 2r²Δρg/9μ, Re = ρvD/μ. Every input has its own unit dropdown, so you can work in SI or imperial units without converting by hand. All math runs in SI internally for maximum precision, then results display in your preferred unit.
KEY FEATURES
• Stokes' Law — solve for drag force, viscosity, radius, or velocity
• Terminal Velocity — solve for Vt, radius, or viscosity with overridable gravity (Earth, Moon, Mars)
• Reynolds Number — instant validity badge tells you when Stokes' Law applies
• Geometry & Mass — sphere volume, surface area, particle mass, settling time, density difference
• Built-in Fluid & Material Database — Water, Air, Glycerin, Honey, Mercury, Engine Oil, Steel, Aluminum, Glass, Copper, Sand, Plastic, Ice, and more
• Add, edit, and duplicate custom fluids and materials
• Calculation History with auto-save, notes, timestamps, and full input snapshots
• Step-by-step worked solutions with substituted values
• Formula reference with assumptions, limitations, and worked examples
PRIVACY FIRST
No accounts. No tracking. No internet required. All calculations and your history stay on-device with SwiftData.
Whether you're modeling sedimentation, sizing particles, studying viscosity, or checking that Stokes' Law applies to your flow regime, Stokes' Law Calculator gives you the answer — and shows the work.
Thank you for your support, and feel free to visit nitrio.com for more apps for your iOS devices.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
- Optimized for the latest devices.
- Fixed minor bugs.
- Improved and redesigned the UI.
The developer, Nitrio, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Tan Chia Ling
- Size
- 1.2 MB
- Category
- Utilities
- Compatibility
Requires iOS 18.6 or later.
- iPhone
Requires iOS 18.6 or later. - iPad
Requires iPadOS 18.6 or later. - Mac
Requires macOS 15.6 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 2.6 or later.
- iPhone
- Languages
English and 8 more
- English, French, German, Japanese, Korean, Portuguese, Simplified Chinese, Spanish, Traditional Chinese
- Age Rating
4+
- 4+
- Copyright
- © Tan Chia Ling
