Oil Tank RouteResidential field tools

Shape-based estimator

Oil tank capacity calculator

Estimate a capacity range from tank shape and measured dimensions. The result shows measurement uncertainty and never claims a model match without a label.

Start the tool Check sources

Field notes

Measure the tank body

  1. 01

    For an obround tank, measure the straight body length plus the full cross-section width and height.

  2. 02

    For a cylinder, enter body length and diameter; the calculator uses the smaller width/height entry as diameter.

  3. 03

    The displayed range assumes +/-0.5 inch measurement uncertainty and excludes wall thickness, fittings, and required headspace.

Capacity / 07

Measure the tank body

The estimator uses the selected shape formula and repeats the calculation at +/-0.5 inch. Values remain in sessionStorage only.

Shared tank data

Verified models available on this route

Granby 204201P Standard 20Plus60 x 27 x 44 in / 275 galGranby Standard 20Plus product table and U.S. vertical capacity chart
Granby 204701P Standard 20Plus60 x 44 x 27 in / 275 galGranby Standard 20Plus product table
Granby 205201P Standard 20Plus72 x 27 x 44 in / 330 galGranby Standard 20Plus product table and U.S. vertical capacity chart
Granby 208101 Standard30 x 27 x 44 in / 138 galGranby Standard residential tank product table and U.S. vertical capacity chart
Roth DWT 1000L43 x 28 x 61 in / 275 galRoth double-wall heating-oil tank dimensions
Roth DWT 1000LH low height51 x 30 x 54 in / 275 galRoth double-wall heating-oil tank dimensions

Route-specific question

One distinction that matters

Why is the result a range instead of one exact gallon number?

Small dimension errors compound across a three-dimensional shape, and external measurements include material that is not liquid volume.

Source boundary

Official source material

Model values require manufacturer support; safety and removal guidance uses official public-agency material. Verification date: 2026-08-02.

  1. Granby Standard 20Plus residential oil tanks

    Manufacturer model dimensions and orientation; verified 2026-08-01.

  2. Granby U.S. vertical tank capacity chart

    Manufacturer gallons-by-inch table, stated precision +/-2%; verified 2026-08-01.

  3. Roth double-wall heating-oil tanks

    Manufacturer nominal capacities and body dimensions; verified 2026-08-01.

Continue the route

Use the next tool only when the job changes.

01 / IdentifyIdentify a tankStart with shape, orientation, label, and dimensions.02 / CompareCompare sizesUse one verified model table shared by every tool.03 / VerifyCheck a 275-gallon tankResolve the most common nominal size without assuming one body shape.