What is Standard Hose Size Connection? | The 3/4″ GHT Standard

You’ve probably grabbed a hose, twisted it onto a spigot, and never thought twice about the threads. They just fit. That’s by design — the standard hose size connection in the United States and Canada is a universal specification called 3/4″ GHT (Garden Hose Thread). Whether your hose is a lightweight 1/2-inch or a heavy-duty 3/4-inch commercial line, the coupling that screws onto the faucet is always the same. Here’s what that standard actually is, how to verify it, and the one mistake that causes most leaks.

What Exactly Is 3/4″ GHT?

The official designation for the standard hose connection is 3/4″–11.5 NH or NHR, as defined by the ANSI/ASME B1.20.1 standard. This is not a tapered pipe thread like NPT. GHT uses a straight (parallel) thread profile with exactly 11.5 threads per inch. The male thread has an outer diameter of approximately 1.0625 inches (26.99 mm). The seal comes from compressing a flat rubber washer inside the female coupling — the threads themselves do not seal the connection.

This standard is used for residential spigots, garden hoses, sprinklers, and nozzles throughout North America. If you’re shopping for a new connection hose that actually fits your spigot, knowing this spec prevents the wrong purchase.

How Does Fitting Size Compare to Hose Diameter?

This is the most common point of confusion. A hose’s inner diameter (ID) — the size of the water passage — does not determine the size of its connector. A 1/2″ hose, a 5/8″ hose, and a 3/4″ hose all use the same 3/4″ GHT fitting. The fitting size is the thread standard, not the hose width.

The hose diameter affects flow rate, not connectivity. A 5/8″ hose delivers roughly 17 gallons per minute, while a 3/4″ hose pushes about 23 GPM. But both will screw onto the same outdoor faucet without an adapter.

How to Measure and Verify Your Hose Thread Size

If you’re unsure whether a fitting is standard GHT, three quick measurements tell you everything.

• Measure the outer diameter of the male thread. Standard GHT measures approximately 1.06 inches (26.99 mm). Anything smaller or larger suggests a different thread standard.
• Count the threads per inch. Place a ruler against the threads and count how many fall within one inch. GHT must have 11.5 threads per inch. NPT pipe threads, by contrast, have 14 TPI at this size.
• Check the thread profile. GHT threads are straight — the diameter stays constant along the fitting. NPT threads are tapered, getting narrower toward the end. A straight thread is your confirmation.

Garden Hose Connection Specs at a Glance

The table shows that regardless of your hose’s water-carrying capacity, the connector is always the same standard. StrongFlex’s complete guide to garden hose fitting sizes provides the same technical breakdown.

The Most Common Mistakes People Make

Three errors cause nearly every connection problem, and they’re all avoidable.

Confusing GHT with NPT. Garden hose thread is straight. Pipe thread (NPT) is tapered. Forcing a GHT fitting onto an NPT thread damages both. If you need to connect a hose to a pipe thread, you need a specific NPT-to-GHT adapter. The standard outdoor spigot at your house uses GHT — your indoor plumbing connections use NPT.

Assuming hose diameter determines fitting size. As covered above, a 5/8″ hose does not need a 5/8″ fitting. Buying a 3/4″ commercial hose for higher flow is fine — it still connects to the standard spigot.

Overlooking the rubber washer. The washer inside the female coupling creates the watertight seal. If it’s missing, worn, or replaced with the wrong thickness, the connection will leak regardless of how tight you crank it. Check the washer before troubleshooting anything else.

3/4″ GHT vs. Other Connection Standards

Each standard serves a different purpose. For outdoor watering in North America, GHT is the only one you need. If you’re connecting a pressure washer, check its inlet — many use GHT with a built-in diffuser, but some require an adapter.

What to Check Before Connecting: Final Checklist

Before you twist on a new hose or attachment, run through this quick check. Confirm the male thread measures about 1.06 inches across. Verify the thread count is 11.5 per inch. Make sure the thread is straight, not tapered. Inspect the female coupling for a flat rubber washer in good condition — no cracks, no missing pieces. If all four checks pass, your connection is standard GHT and should fit any North American spigot without leaks.