These calculators use OIML R 22 from 1975 for mixtures of ethanol and water. Other components, such as sugar, extract, methanol, or dissolved solids, are not included. The formulas apply only within the input ranges shown by each calculator. The density model is limited to −20 to +40 °C and 0 to 100% alcohol. Pressure is not an input to the model and is not corrected. A mathematically valid result does not have to exist as a liquid mixture: the mixture may freeze or change phase at the selected temperature. The app does not check freezing or phase boundaries.

Tables VIIIa, VIIIb, IXa, and IXb assume soda-lime glass with a cubic expansion coefficient of 25 × 10⁻⁶ °C⁻¹. Xa and Xb assume borosilicate glass with 10 × 10⁻⁶ °C⁻¹. XI applies to exactly 100 dm³ of mixture in a steel vessel calibrated at 20 °C, using 36 × 10⁻⁶ °C⁻¹. XII applies to an indicated 100 kg weighed in air with an air density of 1.2 kg/m³ and conventional weights with a density of 8000 kg/m³. Other instruments, materials, or conditions can produce different results.

No result includes the Annex II surface-tension correction. It may be required for alcoholometer or hydrometer measurements and depends on the liquid's surface tension, instrument sensitivity, stem diameter, and density. If the measurement method requires this correction, it must be calculated separately.

The app reproduces the historical OIML R 22 model based on the IPTS-68 temperature scale, not a modern ITS-90/Bettin model. The OIML Bulletin reports model differences in limited cold ranges of up to 0.0035 kg/m³ for Table I and 0.025% vol for Table VIIIb. The app calculates without intermediate rounding and shows more digits than the printed tables, which use one decimal place. R 22 does not define a rounding rule. Old paper tables may also contain rounding, copying, or typesetting errors. An app result may therefore differ from individual printed table values. More displayed digits do not automatically mean the same level of accuracy or a known measurement uncertainty.

Real results can be affected by sample composition, measurement uncertainty, changes in temperature and pressure, instrument calibration, the actual glass expansion coefficient, surface tension, and differences between the model and the real liquid. The app does not calculate measurement uncertainty.

The results are for practical information only. The app is not a verified or certified legal-metrology instrument. For laboratory work, trade, tax, or other legal purposes, use calibrated instruments and officially accepted methods or tables; applicable rules decide whether and how the results may be used. Despite careful implementation, no warranty is given for correctness, completeness, or fitness for a particular purpose. Use is at your own risk.