Dehumidifier Sizing

Dehumidifier pint capacity picker

Pick a space type, square footage, and moisture level — get the DOE 2019+ pint class (22 / 35 / 50 / 70) to shop for, plus the modeled load and a size‑up rule for basements and crawl spaces.

Last verified: 2026-09-08

Portable model covers ~100–2,000 sq ft. Larger spaces get a multi‑unit / whole‑home note.

How damp is it?

Recommended DOE 2019+ class

35‑pint

Methodology, assumptions & sources
  • Lookup, not a formula: the picker reads the same modeled table published on Dehumidifier sizing by space (2026) and rounds your square footage up to the next breakpoint (500 / 1,000 / 1,500 / 2,000 sq ft).
  • Modeled pints/day are anchored to ENERGY STAR capacity bands for portable units under ~2,000 sq ft (20–30 pints/day slightly/moderately damp, 25–40 very damp, 30–50 wet), then translated to the DOE 2019+ retail classes (22 / 35 / 50 / 70 pints) you actually shop for.
  • Basements and crawl spaces are biased toward the upper end of each band because moisture load through the envelope is persistent. If the space stays under ~68°F or you are between bands, the picker also shows a size‑up option.
  • Rated capacity is measured at 65°F / 60% RH (DOE 2019). Real extraction in cooler, drier air will be lower — that is why we round up rather than down.
  • Spaces over ~2,000 sq ft should plan for multiple portable units or ducted whole‑home equipment sized to latent load (Manual J/S) or manufacturer submittals at the design condition.
  • Sources: ENERGY STAR Dehumidifier testing and capacity; DOE test procedure final rule (2023); Frigidaire sizing guide; Aprilaire model coverage table.
  • Independent editorial. Amazon links are affiliate links (tag superbigly-20) — see disclosure.

How to read the result

The number on the box is a DOE 2019+ pint/day class — the rating you will see on today’s retail listings. It is measured at 65°F / 60% RH, which is cooler than the old AHAM 80°F test, so a modern “50‑pint” is roughly what a pre‑2019 “70‑pint” used to be. If you are comparing against an older article or a legacy label, read AHAM vs DOE 2019 ratings first.

“Modeled load” is the pints/day figure from our published sizing table for the nearest square‑footage breakpoint. It is deliberately conservative: we round square footage up, then round the load up to the next common retail class so the unit can cycle rather than run flat out.

When to size up (and when not to)

Full table, assumptions and sources

Every cell the picker reads from is published, with methodology and sources, on Dehumidifier sizing by space (2026). If you disagree with a cell, that page shows how it was derived.