AvGrav Launches: A Modern API Fuel Gravity Calculator for the Ramp
AvGrav, the modernized, field-ready API fuel gravity calculator, is now available on the App Store. Built specifically for aviation line service technicians, FBO operations, and quality assurance personnel, AvGrav replaces the plain, decades-old correction interfaces still common in the field with a real modern app: instant results, a photo-backed history you can trust, and a hands-free Apple Watch companion for calculating right on the ramp.
Built for the People Who Actually Fuel the Ramp
API gravity correction isn't a niche calculation, it's a daily part of quality control for anyone handling aviation and automotive fuel: line service technicians confirming a load before it goes into an aircraft, FBO staff running routine fuel farm checks, and QA personnel documenting that every load meets spec. AvGrav was built directly for that workflow, not adapted from a general-purpose unit converter.
Whether the job is Jet-A, Jet A-1, 100LL, Mogas, or Diesel, AvGrav calculates corrected API gravity at 60°F (15°C) using standard, publicly verified API MPMS Chapter 11.1 / ASTM formulas, the same reference math behind a physical correction wheel, computed instantly instead of read off a printed table.
Hands-Free on the Wrist
The included Apple Watch companion app is built for exactly the moment a phone isn't convenient: hands on a hose, gloves on, mid-check. Enter a reading and get a corrected result without pulling out a phone, keeping the calculation as fast as the physical task it's documenting.
Built to Survive Outdoor Conditions, Not Just a Desk
AvGrav's interface is high-contrast by design, built for readability in direct sun and ramp glare, not a conference room. Results are color-coded (normal, marginal, out of range) so a reading's status is visible at a glance, not just in the number itself.
Documentation, Built In
Every calculation can carry a photo and descriptive text alongside it, turning a single reading into an actual documented record instead of a number that disappears the moment the app closes. A History tab keeps every past calculation available at a glance, and any reading can be sent as a clean, professional export to another device, no separate reporting app or manual write-up required.
AvGrav is a one-time purchase — $3.99, no subscription, no ads, no recurring fees. Equip a line crew with the same tool for the cost of one, with nothing further to manage or renew.
AvGrav is built by the same independent developer behind AvClock, the world clock and airport database for aviation and AvGeeks. Same commitment to a genuinely useful, ad-free, privacy-respecting tool: AvGrav makes no network requests at all, and every calculation and photo stays on the device it was taken on.
AvGrav is a reference and convenience tool, to be used as such, and is not a certified measurement instrument or a substitute for a calibrated physical hydrometer, thermometer, or your organization's official procedures. Always confirm your organization's official procedures, or local laws, before accepting, testing, rejecting, or verifying any fuel load, gravity test, or similar decision.