Pharmaceutical & Laboratory Reference

Ethanol & Isopropanol
Dilution Resources

Rigorous % v/v dilution tools and reference material for ethanol and isopropanol. Ethanol density via the OIML R22 Wagenbreth–Blanke polynomial; isopropanol via International Critical Tables Vol. 3 (1928) extended to 40 °C. Volume contraction is implicitly handled through measured mixture densities.

Calculators

Primary Calculator

Alcohol Dilution Calculator

Mass-based dilution for ethanol and isopropanol. Supports stock-to-target and reverse (target-to-stock) modes. Temperature-corrected densities, volume contraction accounted for.

Ethanol · IPA OIML R22 −20 °C to 40 °C

Polynomial Edition

Alcohol Dilution Calculator 2

Variant of the main calculator with isopropanol density computed from a fitted polynomial rather than lookup tables. Useful for comparing implementations and validating against Perry's tabulated values.

IPA Polynomial Validation tool

Reference

Technical Guide

Alcohol Dilution: A Technical Guide

Comprehensive derivation of the dilution equations, discussion of the Wagenbreth–Blanke density model, isopropanol data sources, worked examples, and notes on volume contraction and measurement uncertainty.

Theory & derivation Worked examples MathJax typesetting

Ethanol–Water Density Tables

Two full-precision density tables: by mass fraction (% w/w) and volume fraction (% v/v, OIML convention, ref. 20 °C). Six temperatures: 15–40 °C. Values computed from the Wagenbreth–Blanke polynomial at full float64 precision.

% w/w & % v/v OIML R22 Float64

Primary Source Data

ICT Isopropanol Density Table

Full transcription of the isopropanol–water density table from the International Critical Tables, Vol. 3 (1928), pp. 120–121. Five temperatures (0, 15×2, 20, 30 °C); data from Turbaba, Doroshevskii, and Lebo. The primary source for Perry’s IPA data and the polynomial fit.

ICT 1928 Primary source 0–30 °C

Data & Source Files

wagenbreth_blanke_oiml_r22.toml

Wagenbreth–Blanke polynomial coefficients from the OIML R22 standard. Machine-readable TOML format; coefficients in Horner nested form as used by the calculators.

External Resources

GitHub Repository

Wagenbreth–Blanke OIML R22 Coefficients

Public repository containing all 54 Wagenbreth–Blanke polynomial coefficients, a validated Python reference implementation, and the canonical TOML coefficient file. Published under CC0. Archived on Zenodo with a permanent DOI.

CC0 DOI: 10.5281/zenodo.19426888