#dipstick

Tank-gauging geometry as an API, computed locally and deterministically. The horizontal-cylinder endpoint computes the liquid volume in a partially-filled horizontal cylindrical tank from the fill height, the radius (or diameter) and the length, V = L·[r²·acos((r−h)/r) − (r−h)·√(2rh−h²)] — the non-linear relationship that makes a horizontal tank read so unintuitively, e.g. a tank filled to a quarter of its diameter holds only about 20 % of its capacity, while half height is exactly half full. The vertical-cylinder endpoint gives the straightforward V = π·r²·h for an upright tank. The sphere endpoint computes the volume in a spherical tank filled to a height h as the spherical cap V = π·h²·(3r−h)/3, exactly half the sphere at h = r. Every response returns the liquid volume in cubic metres and litres, the full capacity, and the fill percentage. All lengths are in metres. Everything is computed locally and deterministically, so it is instant and private. Ideal for industrial, fuel-station, agriculture, water-utility, chemical-storage and process app developers, tank-gauging, dipstick-to-volume and inventory tools, and IoT level sensors. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is tank volume by geometry; for flow rate through a pipe use a flow-rate API.

api.oanor.com/tankvolume-api

Tank volume and fill-level maths as an API, computed locally and deterministically. The volume endpoint gives the total capacity — in litres, US gallons and cubic metres — of a vertical cylinder, horizontal cylinder, rectangular tank, sphere or capsule, from its dimensions in metres, centimetres, millimetres, feet or inches. The fill endpoint computes the volume of liquid and the percent full at a given fill depth, using the exact geometry for each shape — including the circular-segment formula for a horizontal cylinder (where the level is famously non-linear) and the spherical-cap formula for a sphere. The level endpoint is the inverse "dipstick" calculation: it finds the depth that corresponds to a target volume or a target percentage, solving the segment geometry by bisection. Everything is computed locally and deterministically, so it is instant and private. Ideal for fuel, water, oil and chemical tank monitoring, agriculture and irrigation, process and industrial tooling, and tank-gauging and dipstick apps. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is tank-gauging geometry; for swimming-pool volume and chemical dosing use a pool API, and for plain unit conversion use a unit-conversion API.

api.oanor.com/tank-api