Guide · High-pressure hoses and reels
Pressure washer hose diameter and length
A wider, shorter hose loses less pressure. Cat Pumps' and General Pump's loss tables by hose size and flow, and what machines and hose makers list.
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Picks that fit
- Flexzilla HFZPW3425M pressure washer hose, 1/4 in x 25 ft, M22 (14 mm stem)Check price on Amazon
- SIMPSON MorFlex 40226 5/16 in x 50 ft 3,700 PSI cold-water pressure washer hose, M22Check price on Amazon
- SIMPSON Monster Hose 41028 3/8 in x 50 ft 4,500 PSI cold-water pressure washer hose, 3/8 in QCCheck price on Amazon
Short answer
A wider and shorter hose loses less pressure. At 2 GPM, Cat Pumps' table lists about 180 PSI lost per 100 ft of 1/4 in hose, 60 PSI for 5/16 in and 25 PSI for 3/8 in. Loss scales with length, so 50 ft loses half as much. Diameter never decides fit: the end fittings do.
Picks that fitAll picks and how to choose
- Flexzilla HFZPW3425M pressure washer hose, 1/4 in x 25 ft, M22 (14 mm stem)Check price on Amazon
- SIMPSON MorFlex 40226 5/16 in x 50 ft 3,700 PSI cold-water pressure washer hose, M22Check price on Amazon
- SIMPSON Monster Hose 41028 3/8 in x 50 ft 4,500 PSI cold-water pressure washer hose, 3/8 in QCCheck price on Amazon
The friction tables
Water loses pressure to friction as it moves through a hose. How much depends on the hose's inside diameter (ID), its length and the flow.
Cat Pumps' hose friction table shows that at 2 GPM, 100 ft of hose loses about 180 PSI with a 1/4 in ID, 60 PSI with 5/16 in and 25 PSI with 3/8 in.[1] At 3 GPM, the same table lists about 380, 120 and 50 PSI.[1] General Pump prints the same values, and its table also shows about 220 PSI per 100 ft in 5/16 in hose against 90 PSI in 3/8 in at 4 GPM.[2]
| Hose ID | Loss per 100 ft at 2 GPM | at 3 GPM | at 4 GPM |
|---|---|---|---|
| 1/4 in | about 180 PSI | about 380 PSI | Not in our sources |
| 5/16 in | about 60 PSI | about 120 PSI | about 220 PSI |
| 3/8 in | about 25 PSI | about 50 PSI | about 90 PSI |
The 2 and 3 GPM columns are Cat Pumps'; the 4 GPM column is General Pump's. These are reference values for water, not tests of any named hose. Real fittings and the hose's actual ID change the result.
Length
Cat Pumps notes that pressure drop scales with length at a fixed flow, so a 50 ft hose loses half as much as a 100 ft hose of the same ID.[1] The table is in PSI per 100 ft for a given flow, not a percentage of your machine's pressure, so there is no "lose 10% per 50 ft" rule behind it.
Flow matters more than you might expect. In 1/4 in hose, going from 2 to 3 GPM roughly doubles the loss in Cat Pumps' table. Narrow hoses suit low-flow machines better than high-flow ones.
Worked examples (calculated)
These use the tables above and the length rule. They are our arithmetic, not maker figures:
- 50 ft of 1/4 in at 2 GPM: half of 180, so about 90 PSI.
- 25 ft of 5/16 in at 3 GPM: a quarter of 120, so about 30 PSI.
- 50 ft of 3/8 in at 4 GPM: half of 90, so about 45 PSI.
Read flow from your machine's spec at the pressure you actually use, and treat the result as an estimate.
What machines ship with
- SIMPSON MSH3125: a 1/4 in x 25 ft MorFlex hose rated 3,300 PSI, M22 male by M22 female.[3]
- Westinghouse WPX3200: a 3,200 PSI, 2.5 GPM gas washer with a 25 ft, 5/16 in hose and M22 quick-connect connectors, per Westinghouse.[4]
- DEWALT DXPW4440: a 4,400 PSI, 4.0 GPM gas washer with a 50 ft, 3/8 in hose with quick-connect fittings.[5]
Machine pages: SIMPSON MSH3125, Westinghouse WPX3200, DEWALT DXPW4440.
What hose makers offer
- Flexzilla: 1/4 in hoses at 3,100 and 3,600 PSI, and 5/16 in at 3,100 and 4,000 PSI, in 25 and 50 ft.[6] Flexzilla lists no 3/8 in hose.
- SIMPSON: 1/4 in MorFlex at 3,300 PSI, 5/16 in MorFlex at 3,700 and the 3/8 in Monster Hose 80398 at 4,500.[7]
- Obsessed Garage: a 3/8 in hose in 35, 50, 75 and 100 ft, rated 3,000 PSI working pressure.[8]
- DEWALT: the DXPA50PH at 3/8 in x 50 ft, 5,000 PSI,[9] and the DXPA25PH at 5/16 in x 25 ft, 3,700 PSI with M22 connections.[10]
Maker length limits
Some makers cap hose length for a specific machine. Active says replacement hoses for the Active 2.0 should be no longer than 100 ft, steel-braided rubber, with ratings that match the washer's output.[11] Check your manual before adding length.
Diameter is not the fitting
A 3/8 in hose is not a "3/8 in quick-connect" hose by default, and a 1/4 in hose can carry M22 ends. SIMPSON's 3/8 in 41028 has quick-connect plug and socket ends;[12] SIMPSON's 1/4 in MSH3125 stock hose has M22 ends.[3] Choose the ends first, then the widest ID you can get with them.
Hoses by diameter
Picks that fit3 products
For 1/4 in with M22 14 mm ends, choose the Flexzilla HFZPW3425M (25 ft, 3,100 PSI at 70°F).
More on choosing
For 5/16 in with M22 ends, choose the SIMPSON MorFlex 40226 (50 ft, 3,700 PSI; SIMPSON does not state the M22 stem size). For 3/8 in with quick-connect ends, choose the SIMPSON 41028 (50 ft, 4,500 PSI). Each rating must meet or exceed your machine's maximum. On Amazon, check that 'Ships from / Sold by' shows Amazon.com or the brand.
M22 hose with a stated 14 mm stem
Flexzilla HFZPW3425M pressure washer hose, 1/4 in x 25 ft, M22 (14 mm stem)
3/8 in quick-connect hose for cold water
SIMPSON Monster Hose 41028 3/8 in x 50 ft 4,500 PSI cold-water pressure washer hose, 3/8 in QC
SIMPSON lists the MorFlex 40226 as 5/16 in x 50 ft, 3,700 PSI, cold water.[13]
Next
Questions
Is a 3/8 hose better than 1/4?
It loses less pressure. At 2 GPM, Cat Pumps' table lists about 180 PSI lost per 100 ft of 1/4 in hose and about 25 PSI for 3/8 in. It only fits if its end fittings match your machine and gun.[1]
Does a longer pressure washer hose reduce pressure?
Yes. Cat Pumps notes that hose pressure drop scales with length at a fixed flow, so a 50 ft hose loses half as much as a 100 ft hose of the same size.[1]
How long can a pressure washer hose be?
Some makers set a limit for their machine: Active says no longer than 100 ft for the Active 2.0. Otherwise, longer simply means more loss; check your manual.[11]