What size dehumidifier do you need?
Answer three questions and get a pint-per-day capacity recommendation based on the AHAM DH-1-2019 test standard used by ENERGY STAR.
Evidence-checked. Facts and figures on this page are verified against published standards and government sources (AHAM sizing chart, post-2019 DOE test standard). Last verified July 2026 — our methodology.
Recommendation
— pints/day
For spaces below ~65°F, choose a unit with low-temperature/frost control, or a desiccant model — standard compressors ice up in the cold.
Basis: AHAM DH-1-2019 capacity ratings (the post-2019 test standard ENERGY STAR uses). Older pre-2019 pint ratings read ~30% higher for the same machine.
How this calculator works
The recommendation interpolates the AHAM sizing chart (300–3,000 sq ft breakpoints) under the post-2019 DOE test standard. The base capacity is then multiplied by AHAM's published ceiling-height factor (a 10-ft ceiling is ×1.25, a 12-ft ceiling ×1.5), and 5 pints of headroom are added per constant moisture source — indoor laundry drying, or a below-grade location where soil moisture never stops. When a result lands between retail sizes, we round up — an oversized unit cycles off; an undersized one runs forever and never catches up.