Size Of Garden Hose Fitting: Quick Sizing Guide 2026

Most US garden hose fittings use 3/4-inch GHT threads with a rubber washer.
Getting the size of garden hose fitting right stops leaks, protects gear, and saves time. I’ve spent years fixing yards, setting up pressure washers, and building irrigation lines. In this guide, I’ll break down the size of garden hose fitting with simple steps, field tips, and clear answers so you can choose, measure, and connect with confidence.

What the size of garden hose fitting really means

The size of garden hose fitting refers to the thread standard and the nominal size stamped on the coupling. In the US and Canada, the common standard is GHT, also called NH, sized as 3/4-11.5 NH. These are straight threads that seal with a flat washer, not with thread taper.

Most home spigots have a male 3/4-inch GHT outlet. Hoses have a female swivel with a washer on one end and a male GHT on the other. The 3/4 number is nominal. The outside diameter of a male GHT thread is about 1-1/16 inches.

Do not mix GHT with NPT pipe threads. NPT is tapered and seals with thread tape or paste. GHT is straight and seals with a washer. Outside North America, taps and fittings often use BSP threads. That needs a proper adapter. Understanding the size of garden hose fitting helps you pick parts that actually fit.

Common garden hose fitting sizes and where you’ll see them

Here are the sizes and use cases you will meet most:

• 3/4-inch GHT, 11.5 TPI. The North American standard for spigots, hoses, nozzles, and sprinklers.
• Hose inner diameters. 1/2 inch for light-duty, 5/8 inch for most homes, 3/4 inch for high flow and long runs. This is hose bore, not thread size.
• Quick-connects. Bodies are labeled for 3/4-inch GHT. They snap over existing GHT male or female ends.
• Adapters. GHT to NPT (for pumps, filters, pressure washers), and GHT to BSP (for EU or UK taps).
• Specialty. 1-inch garden and fire fittings exist in farms and commercial yards. These are not typical at home.

If you shop by region, match standards. North America uses GHT. The UK and EU use BSP. Always check the product sheet or bag label.

How to measure the size of garden hose fitting at home

You can confirm the size of garden hose fitting in minutes with simple tools.

1. Check the thread type. If your hose seals with a flat washer, it is almost always GHT/NH.
2. Measure the male thread outside diameter. Use a ruler or caliper. A 3/4 GHT male measures about 1.06 inches (1-1/16).
3. Count threads per inch. GHT has 11.5 TPI. Lay a ruler across 1 inch of threads and count peaks. If you see about 11 to 12, it matches GHT.
4. Inspect the washer. A garden hose needs a flat washer or O-ring to seal. If the washer is missing, it will leak no matter the size.
5. Identify hose bore. Look on the hose jacket for 1/2, 5/8, or 3/4. That is flow capacity, not thread size.
6. For pipe ports, check markings. NPT parts say 1/2 NPT or 3/4 NPT. Do not force them onto GHT.

Tip from the field: I keep a spare male 3/4 GHT cap in my toolbox. If it threads on clean and smooth, I know the spigot is GHT. If it binds, I stop and test for BSP or NPT adapters. This simple step avoids cross-threading and damage.

Compatibility, adapters, and regional standards

The size of garden hose fitting is easy when you stay within one system. Problems start when you cross systems.

• GHT to NPT. Use a labeled adapter. For example, 3/4 GHT female to 1/2 NPT male. Seal NPT with PTFE tape or pipe dope. Do not tape GHT.
• GHT to BSP. Use a BSP-to-GHT adapter. BSP has a different thread angle and pitch. For 3/4 BSP, the pitch is 14 TPI. It will not mate with 11.5 TPI GHT.
• Quick-connect systems. Buy full sets designed for GHT. Mixing low-cost plastic connectors with metal bodies from another brand can cause drips.

If you import a hose or nozzle, plan on adapters. I have set up travel rigs for RVs and rentals. One good brass BSP-to-GHT adapter saved many trips to the store.

Flow, pressure, and performance

The size of garden hose fitting affects how much water you get at the tool. Bigger hose bores and shorter lengths give more flow and less pressure drop. The fitting must match that plan.

As a rule of thumb, a 5/8-inch hose is the sweet spot for home use. It balances weight, cost, and flow. A 3/4-inch hose and fittings shine for long runs, big sprinklers, or feeding a pressure washer inlet. A 1/2-inch hose feels light but chokes high-flow gear.

Real-world note: I run a 3/4-inch hose from the spigot to a Y splitter, then 5/8-inch lines to sprinklers. This small change kept heads popping up fast and even. If you see weak spray, reduce hose length or step up hose bore before blaming pressure.

Materials, sealing, and thread care

Thread material matters as much as the size of garden hose fitting.

• Brass. Durable, repairable, corrosion-resistant. My default pick for spigots and adapters.
• Stainless steel. Strong and corrosion-proof. Great for marine or hard water, but costs more.
• Aluminum. Light and strong, but can gall on brass. Use with care.
• Plastic. Light and cheap. Fine for quick swaps, but threads wear sooner.

Care tips that stop leaks:

• Replace flat washers each season. Keep spares in a zip bag.
• Hand-tighten only. A gentle snug with pliers is okay, but do not crush the washer.
• Use PTFE tape on NPT only. Never on GHT-to-GHT joints.
• Cap outdoor threads in winter. This keeps grit out and saves the first seal of spring.

Mistakes to avoid and pro tips from the field

Here are the pitfalls I see most when people guess the size of garden hose fitting.

• Mixing GHT and NPT by force. The seal fails, and threads deform. Always use an adapter.
• Blaming tape. Leaks at GHT do not need tape. They need a good washer or a fresh O-ring.
• Under-sizing the hose. A 1/2-inch hose on a long run starves high-flow sprinklers. Use 5/8 or 3/4 instead.
• Cheap quick-connects. Thin plastic collars crack. Invest in brass sets for daily use.
• Cross-threading the spigot. Start every connection by hand. If it resists, back off and realign.

Pro tip: Color-code adapters. I paint a tiny stripe on BSP adapters so they never get mixed into my GHT bin. It has saved me many return trips.

Buying guide and quick checklist

Use this checklist to dial in the right size of garden hose fitting and avoid guesswork.

• Confirm your region. GHT in North America, BSP in many other countries.
• Check spigot thread. 3/4 GHT male is typical at home.
• Match hose bore to job. 5/8 inch for most yards, 3/4 inch for long runs or high flow.
• Plan adapters. List every device port: pump inlets, filters, timers, pressure washers.
• Choose materials. Brass for durability, stainless for harsh sites, plastic for light duty.
• Stock consumables. Flat washers, O-rings, and two or three critical adapters.
• Test for leaks. Run water, tighten by hand, inspect the washer seat, and recheck after 10 minutes.

If the project crosses systems or regions, buy adapters first. This single step locks in the right size of garden hose fitting and keeps your build on track.

Frequently Asked Questions of size of garden hose fitting

What is the standard garden hose thread size in the US?

It is 3/4-11.5 NH, also called 3/4-inch GHT. These are straight threads that seal with a flat washer.

Is 5/8 inch the fitting size or the hose size?

5/8 inch is the hose inner diameter, not the thread size. The fitting is still 3/4-inch GHT on most hoses.

Can I connect NPT pipe threads to a garden hose?

Yes, with a proper adapter that converts GHT to NPT. Seal the NPT side with PTFE tape or pipe dope, and rely on the washer on the GHT side.

Why does my hose leak even when it feels tight?

The flat washer may be missing, cracked, or deformed. Replace the washer, hand-tighten, and make sure the faces are clean and square.

Do quick-connects reduce flow?

Good brass quick-connects have little impact on flow. Cheap plastic sets can narrow the path and add restriction.

How can I tell if a faucet is BSP and not GHT?

Measure thread pitch and count TPI. A 3/4 BSP has about 14 TPI and will not match the 11.5 TPI of GHT.

Conclusion

Choosing the right size of garden hose fitting is simple once you know the standard, how to measure, and when to use adapters. Match GHT to GHT, use washers, and size your hose bore for the job. This keeps your system tight, your tools happy, and your weekends free.

Put this guide to work on your next setup. Check your spigot, pick the right adapters, and upgrade any weak links today. If you found this helpful, share it, subscribe for more field-tested tips, or drop your questions in the comments.