# Gammon API Gravity Calculator > Digital calculator for fuel API gravity and total weight. (iPhone/iPad app by Gammon Technical Products.) - Source: https://appshunter.io/ios/app/gammon-api-gravity-calculator/id1163782117 (this page in markdown: same URL + `.md`) - Developer: [Gammon Technical Products](https://appshunter.io/developer/1163782116) - Category: Reference, Utilities - Price: $9.99 - Rating: 3.60/5 from 10 App Store ratings · 8 written reviews indexed - Age rating: 4+ - Requires: iOS 8.0 · 10 MB - Languages: American English - Released: 2016-11-08 - Data updated: 2026-09-07 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/gammon-api-gravity-calculator/id1163782117/reviews.md ## What is Gammon API Gravity Calculator? The GTP API Gravity Calculator from Gammon Technical Products, Inc. provides users the ability to determine corrected API at 60 Deg F for jet, gasoline, and diesel fuels. The calculator is a digital version of our GTP-3012-1A and GTP-2727EF slide calculators and it also is capable of calculating the total weight of the fuel. ## Key features - Corrected API gravity calculation - Fuel weight calculation - Supports jet, gasoline, and diesel fuels - Digital slide calculator replacement - Accurate at 60°F ## Chart rankings - #78 in Top Paid · Reference (US App Store) ## Recent user reviews (8 of 8) All indexed reviews: https://appshunter.io/ios/app/gammon-api-gravity-calculator/id1163782117/reviews.md ### 3/5 — Works … where’s 100LL *2026-01-06* This app works great, buts it’s missing 100LL for aviation use. This will get a FIVE STAR when this comes out. ### 1/5 — Overpriced *2025-10-13* $10 for a simple calculator is absurd ### 5/5 — Quick & Simple *2025-03-07* For many years I’ve been using this app when receiving fuel and always found it to be quick, simple and accurate. Many times I’ve checked the app against the wheel calculator and found the results identical. In fact, the wheel calculator can easily be misaligned or misread. We also keep the wheel calculator on hand and run calculations on it and on the app before rejecting a fuel load. ### 5/5 — Quick & Simple *2023-09-06* I’ve been testing aviation fuel for nearly 10 years. Bought this app 3 years ago. It is great! Much easier and quicker than the wheel. ### 5/5 — I use this daily *2020-12-04* I use this app on a daily basis. I used to haul Jet A, so we’re always having to sample before offloading. Yeah there was a time or two where I was .01 or .02 off from the receivers wheel, but not far enough off for them to reject the load. I now haul gasoline, and utilize this app for loading my truck based off of the gravity/weight of the fuel. I will find out what the gravity is, enter it in and the see how many gallons I can load based off of the weight. I’ve been able to load anywhere from 50 gallons to 500 gallons more then I used to haul. Bigger payload equals more money. I was really hesitant at first loading my truck this way, so I slowly started adding 50-100 gallons to verify the weight calculations. I’ve been doing it this way now for a few months and haven’t had any problems with going through weight stations. I’m always within a couple hundred pounds of what I can legally gross. As far as other things the previous reviews said, I agree with the waste of space on the screen and small numbers. As far as selecting the type of fuel, I had that problem at first also. But it’s actually irrelevant anyway, it doesn’t matter if you’re dealing with jet, diesel or gasoline, the numbers always come out the same as long as you enter them correctly. ### 4/5 — Works great but could use a better UI *2019-02-02* This works great and I double checked with the wheel, though this could use a better user interface look. There is much unused white space in the app where they could have made the text and input boxes larger to scale with screen, because the numbers are small. ### 2/5 — DOES NOT MATCH GTP-3012 *2018-04-28* I purchased this for easier reading of API Gravity readings when receiving fuel loads. I’ve checked it a few times against the “wheel” and it’s been .02 to .04 higher with each reading. That can result in a rejected load of fuel. Spent $10 on a item I can’t rely on. ### 1/5 — Doesn't work *2017-03-11* Doesn't work. Can't select fuels. ## Frequently asked questions about Gammon API Gravity Calculator ### What is the Gammon API Gravity Calculator used for? The Gammon API Gravity Calculator is used to determine the corrected API gravity for jet, gasoline, and diesel fuels at 60°F. It can also calculate the total weight of the fuel. ### How accurate is the Gammon API Gravity Calculator? The app provides corrected API gravity at 60°F, replicating the accuracy of physical slide calculators. It has a user rating of 4.0 stars from 8 ratings. ### What types of fuel can the Gammon API Gravity Calculator handle? The calculator is designed to work with jet fuel, gasoline, and diesel fuels. ### Is the Gammon API Gravity Calculator available on Android devices? Based on the provided data, the Gammon API Gravity Calculator is supported on iPhone and iPod devices. ### How much does the Gammon API Gravity Calculator cost? The Gammon API Gravity Calculator is a paid application, priced at $9.99. ### When was the Gammon API Gravity Calculator last updated? The Gammon API Gravity Calculator was last updated on November 8, 2016, with version 1.0. ### What is the age rating for the Gammon API Gravity Calculator? The Gammon API Gravity Calculator has an age rating of 4+, making it suitable for a wide range of users. ### Does the Gammon API Gravity Calculator have ads? No, the Gammon API Gravity Calculator does not contain advertisements, as indicated by the 'hasAds' flag being false. ## Version history (last 1 release) ### 1.0 — 2016-11-08 This update from Apple will improve the functionality of this app. No new features are included. ## Apps similar to Gammon API Gravity Calculator | App | Rating | Price | Category | | --- | --- | --- | --- | | [S61 PPC](https://appshunter.io/ios/app/s61-ppc/id1559628963) | — | $2.99 | Reference | | [API Pipe Properties](https://appshunter.io/ios/app/api-pipe-properties/id1044718618) | — | $1.99 | Reference | | [OilField Hydrostatic Pressure.](https://appshunter.io/ios/app/oilfield-hydrostatic-pressure/id921528975) | — | $0.99 | Reference | | [ASTM 6B Table](https://appshunter.io/ios/app/astm-6b-table/id6480513283) | — | $1.99 | Reference | | [Oilfield: Gravity & Flow Calc](https://appshunter.io/ios/app/oilfield-gravity-and-flow-calc/id6740396322) | — | $1.99 | Reference | ## More apps by Gammon Technical Products - [GTP API Gravity Calculator2](https://appshunter.io/ios/app/gtp-api-gravity-calculator2/id6742924006) All apps by Gammon Technical Products: https://appshunter.io/developer/1163782116 ## Related topics [gammon api gravity calculator](https://appshunter.io/ios/topics/gammon-api-gravity-calculator) · [gammon technical products](https://appshunter.io/ios/topics/gammon-technical-products) · [gammon](https://appshunter.io/ios/topics/gammon) --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-09-07.*