Hose Sizes: How Many mm Are 1/2, 5/8, 3/4 and 1″?
Choosing between 1/2" and 3/4" hose can be confusing. An inch label may describe a nominal hose size or a connection size, so check the actual internal diameter, outside diameter, wall thickness and fittings together. This guide explains common hose sizes, their millimetre conversions and how to check tap and spray-nozzle compatibility.
Explore the relevant options: 1/2″ garden hose options · 3/4″ garden hose options
What are 1/2", 5/8", 3/4" and 1" in millimetres?
| Inch expression | Approx mm | Daily use |
|---|---|---|
| 1/2" | 12.7 mm | Small tap and balcony lines |
| 5/8" | 15.9 mm | Garden hose and medium flow |
| 3/4" | 19.05 mm | High flow garden and washing |
| 1" | 25.4 mm | Higher flow and main line |
These are mathematical conversions of the nominal inch dimensions. Before buying, confirm the actual internal diameter in the product data sheet and the required connection size. The difference between internal and outside diameter varies across braided, thermo and spiral-reinforced hoses.
Is inner diameter or outer diameter more important?
Internal diameter and hose length are central to flow calculations. Outside diameter affects the choice of clamps, fittings and openings the hose must pass through. Two hoses with the same outside diameter can have different internal flow areas if their wall thicknesses differ.
How do I check compatibility with the tap, spray nozzle and connector?
- Determine the thread size at the faucet or pump outlet.
- Measure the actual inside diameter of the hose.
- Compare the outer diameter of the nipple or fitting that will fit into the hose end.
- Make sure the clamp can tighten the hose without crushing it.
- Test the connection under water with gradual pressure.
Unnecessary throttling can reduce flow, even with a short adapter. flow and pressure calculation guide Consider with connection selection.
Which size makes more sense for which job?
For short balcony or garden runs, 1/2" hose may be considered; compare 5/8", 3/4" or 1" sizes where more flow is required. Selection depends on available supply, length, nozzle and the verified hose pressure rating. A matching diameter does not make a garden hose suitable for a pressure washer’s high-pressure discharge line.
Clear choice; It is made according to the tap pressure, meter, gun/sprinkler flow rate and the storage condition of the hose. garden hose models Examine the product class and meter option together on the page.
Why might a longer hose need a larger internal diameter?
Friction loss increases with hose length and becomes more significant with a narrow internal diameter. A spray nozzle that performs well on a short hose may deliver less flow through a 50 metre run. An unnecessarily large diameter also adds handling effort and cost, so assess it against the required flow.
Short checklist of 8 items when choosing dimensions
- Write down the usage area and fluid of the hose.
- Measure faucet/pump output.
- Determine target flow rate and approximate meters.
- Verify the inner diameter from the technical sheet.
- Note the sun, frost and temperature condition.
- Select the sleeve, clamp and gun to the same size.
- Plan roll and storage space.
- State the unit of measurement clearly in the quote.
Related products, dimensions and technical guides
Frequently Asked Questions
These 18 questions cover the meanings of 1/2", 5/8", 3/4" and 1" hose sizes, their millimetre conversions and the checks needed for the intended application.
What is 1/2" hose in millimetres?
1/2" converts to 12.7 mm. Confirm the actual hose internal diameter and the connector size in the product specifications.
What is 5/8" hose in millimetres?
5/8" is approximately 15.9 mm. Garden hose may have nominal size; actual inner diameter and connection type are also checked.
What is 3/4" hose in millimetres?
3/4" converts to 19.05 mm. It may suit a higher required flow, but it must be checked with the tap and spray-nozzle passages.
What is 1" hose in millimetres?
1" equals 25.4 mm. The product’s actual internal diameter may differ; check its technical dimensions.
Can a 3/4" hose connect to a 1/2" tap?
It can be installed with the appropriate fitting or adapter. Any adapter should not be used without checking the flow rate and sealing effect of the throttle.
Why is the inner diameter of the garden hose important?
It is the inner diameter that determines the water flow cross section. The outer diameter is more important for clamp and connection part compatibility.
Does hose size affect flow rate?
Yes. As the inner diameter decreases for the same length and pressure, friction loss may increase and usable flow rate may decrease.
What size to choose for 20 meter garden hose?
It varies depending on tap pressure, gun flow rate and place of use. The short pot line and the sprinkler line may not require the same size.
Will 1/2 size be sufficient for 50 meter hose?
It may happen if the target flow is low; However, long or even narrow internal diameters may increase loss. Flow and pressure calculations must be made.
How to measure the outer diameter of the hose?
It is measured from the outer surface with a caliper. For the inner diameter, the inner opening of the hose end is measured; Wall thickness is also noted.
How to choose a hose fitting?
The tap thread, hose inner diameter and the part of the fitting entering the hose are compared together.
Does inch measurement change in braided hose?
Although the nominal connection remains the same, mesh and wall thickness can change the actual inside/outside diameter. Product technical size is taken as basis.
Can you wash a car with a 1/2 hose?
It can be used for short and low flow rates; In long line or pressure washing, target flow rate and gun compatibility should be checked.
Does water pressure increase as the hose diameter increases?
The hose alone does not produce pressure. Larger internal diameter can reduce loss, but source pressure and pump capacity are decisive.
What do inches mean in hose dimensions?
In most products, it describes the nominal connection or pipe size. The product sheet should be read for the actual inner and outer diameter.
Why does the hose tip leak?
Wrong fitting, loose/too tight clamp, cut end or mismatched gasket can cause leakage.
How to write the hose size when receiving a quote?
Write inches, approximately mm, inner diameter, outer diameter, total meters and connection type together.
What hose sizes does Ertunç Plastik offer?
There are different inner diameter and meter options depending on the product family. Verify current size and price on the relevant product page or with the quote team.
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