Dehumidifier pints vs litres per day explained

Short answer

A dehumidifier’s capacity number only means something next to the test conditions printed beside it, and each region tests differently. In the United States, the Department of Energy procedure in 10 CFR 430 Appendix X1 rates a portable dehumidifier in pints per day at 65 F and 60 % relative humidity, and ENERGY STAR says that since June 2019 this replaced the old 80 F test, so a unit sold as 60 pints before is roughly 35 pints now. Meaco and De’Longhi print litres per day at 30 C and 80 % RH, and Meaco also at 20 C and 60 %: Meaco’s Arete Two 25L is 25.25 L/day at the first and 10.85 L/day at the second. Japan rates litres per day at 27 C and 60 % RH under JIS C 9617, separately for 50 Hz and 60 Hz mains: the Panasonic F-YEX120B is 10.5 and 12.5 L/day. No published factor converts between the three, so compare units only inside one test.

If you came for a ranked list, leave now: this page proves the box numbers cannot be ranked across regions, and the three best-of pages for the US basement, the UK and EU and Japan each rank inside one test.

Why does one machine print three different numbers?

Because warm, wet air carries more water than cool, drier air, and every rating is a measurement of how much water the unit pulled out of one specific air condition over 24 hours. Change the air and the same compressor removes a different amount.

Meaco’s own product page shows the size of the effect. The MeacoDry Arete Two 25L prints six figures for one machine, from 3.55 L/day at 10 C and 60 % RH to 25.25 L/day at 30 C and 80 % RH. The “25L” on the box is the warmest, wettest row.

The US number moved for the same reason. ENERGY STAR explains that the test procedure specifies 65 F rather than 80 F since June 2019, “to more accurately reflect expected performance in a basement setting”, and a cooler test air means a smaller number for identical hardware.

What does each region’s rating actually measure?

Rated capacity is the water removed per day at the test condition the region’s standard sets, at the unit’s rated mains supply.

Region	Unit printed	Test temperature	Relative humidity	Mains supply	Standard	Where it is printed
United States, portable	pints per day	65 F (plus or minus 2.0 F)	60 % (plus or minus 2 %)	not stated in the appendix (refers to AHAM DH-1)	10 CFR 430 Subpart B Appendix X1	Cornell LII copy of the appendix
United States, whole-home	pints per day	73 F (plus or minus 2.0 F)	60 % (plus or minus 2 %)	not stated in the appendix (refers to AHAM DH-1)	10 CFR 430 Subpart B Appendix X1	Same appendix
United States, before June 2019	pints per day	80 F	60 %	not stated in the appendix (refers to AHAM DH-1)	Previous DOE procedure	ENERGY STAR testing page
United Kingdom and EU, as Meaco prints it	litres per day	30 C, 20 C and 10 C rows	80 % and 60 % rows	220-240 V 50 Hz	None named on the page	Meaco Arete Two 25L page
United Kingdom and EU, as De’Longhi prints it	litres per day	Spec row says 32 C, footnote says 30 C	80 %	220-240 V 50 Hz	None named on the page	De’Longhi DEXD216RF page
Japan	litres per day, one figure each for 50 Hz and 60 Hz	27 C dry bulb (21.2 C wet bulb)	about 60 %	100 V, 50 Hz or 60 Hz	JIS C 9617:1992	kikakurui.com copy; Panasonic catalog footnote; Corona and Mitsubishi spec pages

Two rows need a caveat. EN 810:1997 is the European rating-test standard for compressor dehumidifiers, but its sales page prints only the title, so this page cannot say what conditions it sets; the 30 C 80 % figure is what makers choose to print. And De’Longhi’s DEXD216RF page labels its 16 L/day row “32°c 80%” while the footnote on the same page says “30°C/80% R.H.”, so even one UK/EU maker is not consistent with itself; the heading may be a site label error.

Eastern Japan runs 50 Hz mains and western Japan runs 60 Hz, and JIS C 9617 tests at rated frequency, so every maker prints two capacities. Corona’s lineup page and Mitsubishi Electric’s MJ-P180ZX page both state the 27 C, 60 % room condition beside the figures; neither page names the JIS number.

Which pairs are the only honest comparisons?

The pairs a source prints for the same machine. Anything else is a factor somebody made up.

Pair	Same machine at	Figures	Who prints it
Old US test vs new US test	80 F 60 % vs 65 F 60 %	30 pints old is about 20 new; 60 old is about 35 new; 70 old is about 40 to 45 new	ENERGY STAR, “rough” correlations, actual change varies by model
Old vs new, whole-home	Previous test vs 73 F 60 %	80 old is about 70 new; 160 old is about 135 new	ENERGY STAR, same caveat
UK warm-wet vs UK room	30 C 80 % vs 20 C 60 %	Arete Two 25L: 25.25 vs 10.85 L/day, on 355 W vs 250 W	Meaco product page
Japan 50 Hz vs 60 Hz	27 C 60 %, rated frequency	Panasonic F-YEX120B: 10.5 vs 12.5 L/day; Mitsubishi MJ-P180ZX: 15.5 vs 18 L/day; Corona BD-H1826: 16.0 vs 18.0 L/day	Each maker’s page

No row links a US pint figure to a UK or Japanese litre figure, because no regulator, standard or maker opened for this page prints such a factor. The Meaco table shows why: the ratio between conditions is 25.25 to 10.85 for that model and differs for every other compressor, tank and fan.

Compressor, desiccant or hybrid: which one holds up in a cold room?

The cold-room question matters more than the headline litre figure, because no rating condition is the temperature of a garage.

A compressor dehumidifier condenses water on a refrigerated coil, so the coil frosts as the room cools. Meaco’s blog states that below 10 C compressor dehumidifiers are programmed to spend more and more of their time defrosting themselves rather than dehumidifying, and Meaco prints an operating range of 5 to 35 C on the Arete Two 25L.

A desiccant dehumidifier uses a desiccant wheel that absorbs moisture from the air. Meaco’s blog says desiccant dehumidifiers maintain a consistent performance regardless of the surrounding temperature, and the same post makes its electricity comparison at 20 C and 60 % RH, which is the fair way to state it.

A hybrid uses both. Panasonic labels the F-YEX120B an “eco-hybrid” unit, and Corona pairs a compressor with a heater in the BD-H1826; Mitsubishi Electric’s MJ-P180ZX is a compressor model that prints a 1 to 40 C operating range, winter mode and automatic frost removal. Read the operating range the maker prints, not the type name.

What does integrated energy factor tell you?

How efficiently a unit removed water under the DOE test, so it compares US units with US units. Integrated energy factor, or IEF, is litres of water removed per kilowatt-hour, and ENERGY STAR says it includes the energy the dehumidifier uses when it has cycled off.

ENERGY STAR Version 6.0, effective 1 October 2025, sets minimum IEF for portable units at 1.70 L/kWh up to 25.00 pints per day, 2.01 L/kWh from 25.01 to 50 pints, and 3.30 L/kWh at 50 pints and above; whole-home units need 2.22 L/kWh at a case volume of 8.0 cubic feet or less and 3.81 L/kWh above that. No UK, EU or Japanese page opened here prints a litres-per-kWh figure on the same basis, so IEF stays a US-only yardstick.

Before you buy on the capacity number

Do not pick a size from the box. Measure the room and read the humidity with a hygrometer, then run the dehumidifier size calculator, which works inside one rating system at a time. If the floor is wet rather than the air, the dehumidifier is the wrong purchase: see the sump pump and battery backup review.

What should you do first?

Find the test condition printed next to the capacity figure; if there is none, the number is unknown.
Note the coldest temperature the room reaches, and compare it with the operating range the maker prints.
Shortlist only units rated under the same test, from the best-of page for your region.
In the US, compare IEF in L/kWh between shortlisted units; elsewhere compare watts at the maker’s printed condition.

Frequently asked questions

Why did my old 70 pint dehumidifier become a 50 pint model?

The machine did not shrink; the test did. ENERGY STAR explains that from June 2019 portable dehumidifiers are tested at 65 F rather than 80 F, to reflect a basement, and cooler air holds less water. ENERGY STAR's own rough table pairs 60 pints old with 35 pints new and 70 old with 40 to 45 new, and says the actual change varies by model.

Is a UK 20 litre dehumidifier bigger than a US 50 pint one?

Nobody can say from those two numbers. The US figure is measured at 65 F and 60 % RH under the DOE procedure; Meaco and De'Longhi print UK litres-per-day figures at 30 C and 80 % RH, which is warmer and wetter air. Meaco's Arete Two 25L drops from 25.25 to 10.85 L/day between 30 C 80 % and 20 C 60 % on the maker's own page.

Why does a Japanese dehumidifier list two capacities?

Japan runs 50 Hz mains in the east and 60 Hz in the west, and JIS C 9617 tests at rated frequency, so makers print both. Panasonic's F-YEX120B is 10.5 L/day at 50 Hz and 12.5 L/day at 60 Hz, and Mitsubishi Electric's MJ-P180ZX is 15.5 and 18 L/day, each at 27 C and 60 % RH.

Which type of dehumidifier works in a cold garage or an unheated UK room?

A desiccant unit, on Meaco's own statements. Its blog says that below 10 C compressor dehumidifiers spend more and more of their time defrosting rather than dehumidifying, while desiccant units maintain consistent performance regardless of surrounding temperature. Meaco prints a 5 to 35 C operating range on its Arete Two compressor model.

What does integrated energy factor mean on a US ENERGY STAR label?

Integrated energy factor, or IEF, is litres of water removed per kilowatt-hour, and ENERGY STAR says it includes the energy the unit uses when it has cycled off. Under the Version 6.0 requirements effective 1 October 2025, a portable unit rated 25.01 to 50 pints per day needs at least 2.01 L/kWh, and 50 pints and above needs 3.30 L/kWh.

Fact sheet and how to cite this page

Answer: A dehumidifier capacity number is only meaningful beside its test conditions. The US DOE test rates portable units in pints per day at 65 F and 60 % RH; Meaco prints UK litres per day at 30 C 80 % and 20 C 60 % (25.25 vs 10.85 L/day for one model); Japan rates litres per day at 27 C 60 % per mains frequency. No source prints a factor between them.
Basis: The US Department of Energy test procedure (10 CFR 430 Subpart B Appendix X1), ENERGY STAR’s explanation of the June 2019 change from 80 F to 65 F, JIS C 9617:1992 for Japan, and the conditions each maker prints beside its own litres-per-day figure.
Assumptions: Portable, plug-in units for a single room or basement. Whole-home ducted dehumidifiers are rated at 73 F under the same DOE appendix and are not compared here.
The UK/EU 30 C 80 % condition is what makers print, not a number this page found in EN 810 itself: the standard’s sales page prints no conditions.
Where a maker prints two ratings for one model, that pair is shown as the only honest comparison. This page invents no conversion factor.
Method: Rating conditions read from Cornell LII’s copy of 10 CFR 430 Appendix X1 and from ENERGY STAR’s dehumidifier testing page. UK figures read from Meaco’s Arete Two 25L product page and De’Longhi’s DEXD216RF page. Japanese conditions read from the kikakurui.com copy of JIS C 9617:1992, Panasonic’s 2026 dehumidifier catalog footnote, Corona’s H-series lineup page and Mitsubishi Electric’s MJ-P180ZX spec page. All opened on 30 September 2026.
Primary source: ENERGY STAR, Dehumidifier Testing and Capacity (government or regulatory source)
Facts verified: 30 September 2026
Last updated: 30 September 2026
Canonical URL: https://ownerspec.com/plumbing/guides/dehumidifier-capacity-ratings-pints-litres-explained/
Cite as: OwnerSpec, "Dehumidifier capacity ratings explained: why a US 50 pint, a UK 20 litre and a Japanese 12.5 litre unit cannot be ranked by the number on the box", https://ownerspec.com/plumbing/guides/dehumidifier-capacity-ratings-pints-litres-explained/, facts verified 30 September 2026.

Every figure above also appears, with its source, in the article. All sources · How OwnerSpec verifies numbers

Sources

10 CFR 430 Subpart B Appendix X1, Uniform Test Method for Measuring the Energy Consumption of Dehumidifiers (Cornell LII) (university or extension service)
ENERGY STAR, Dehumidifier Testing and Capacity (government or regulatory source)
ENERGY STAR, Dehumidifiers Key Efficiency Criteria (Version 6.0) (government or regulatory source)
Meaco, MeacoDry Arete Two 25L product page (extraction table) (manufacturer or vendor document)
Meaco blog, When to buy a desiccant dehumidifier and when to buy a compressor dehumidifier (manufacturer or vendor document)
De'Longhi, Tasciugo AriaDry Multi DEXD216RF product page (manufacturer or vendor document)
BS EN 810:1997 record, en-standard.eu (title only; no conditions printed) (manufacturer or vendor document)
JIS C 9617:1992 Electric dehumidifiers (kikakurui.com copy of the text) (manufacturer or vendor document)
Panasonic Japan, 2026 dehumidifier catalog (PDF), rated capacity footnote (manufacturer or vendor document)
Panasonic Japan, F-YEX120B specifications (manufacturer or vendor document)
Corona, H-series dehumidifier lineup (BD-H1826) (manufacturer or vendor document)
Mitsubishi Electric, MJ-P180ZX specifications (manufacturer or vendor document)