Antoine Vapor Pressure Calculator

Computes vapor pressure using the Antoine equation log₁₀(P_mmHg) = A − B / (C + T_C) for twenty common process chemicals. Paste a CSV of compound / temperature pairs and retrieve P in mmHg, psia, kPa, and bar.

CSV Input

Reference: Antoine constants from NIST Chemistry WebBook, Perry's Chemical Engineers' Handbook 9th Ed., and Yaws' Handbook of Vapor Pressure. The Antoine equation is accurate within the validated temperature range; extrapolations are flagged. For compounds not in the built-in database, run the Python script locally and extend ANTOINE_DB.

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