What size is a garden hose fitting?
Standard garden hose fitting size
The standard garden hose fitting size in the United States and Canada is 3/4 inch, 11.5 threads per inch, designated as 3/4"-11.5 NH (or NHR). This universal thread size applies to virtually all residential and most commercial garden hoses, spigots, nozzles, sprinklers, and other watering accessories. Regardless of the hose's interior diameter, the threaded coupling on each end is almost always this same standard size.
| Specification | Details |
|---|---|
| Standard thread size | 3/4"-11.5 NH (NHR) |
| Thread designation | GHT (Garden Hose Thread) |
| Threads per inch | 11.5 TPI |
| Outer diameter of male thread | 1-1/16" (approximately 1.0625") |
| Governing standard | ANSI/ASME B1.20.7 |
| Compatible countries | United States and Canada |
This standardization is set by the American National Standards Institute (ANSI). The abbreviation NH stands for "American Standard Hose Coupling Threads of Full Form," used for machined threads. NHR stands for "American Standard Hose Coupling Threads of Rough Form," used for garden hose couplings made via casting or molding rather than precision machining.
You may also see this thread size referred to as GHT (Garden Hose Thread). GHT, NH, and NHR all describe the same standard thread specification. This means any garden hose you buy at a hardware store will connect to any standard outdoor faucet, nozzle, or sprinkler without needing an adapter.
Many people confuse the interior diameter of a garden hose with the fitting thread size. The interior diameter (how wide the hose is inside) determines water flow volume. The fitting thread size (the threaded connector on each end) determines what the hose connects to. These are two completely different measurements.
Garden hose thread vs. pipe thread
Garden hose thread (GHT) and national pipe thread (NPT) are not interchangeable. GHT uses straight, parallel threads, while NPT uses tapered threads that wedge tighter as they're screwed together. Attempting to force-connect a GHT fitting onto an NPT fitting will damage both threads and cause leaks.
| Feature | GHT (Garden Hose Thread) | NPT (National Pipe Thread) |
|---|---|---|
| Thread type | Straight (parallel) | Tapered |
| Common sizes | 3/4"-11.5 | 1/2", 3/4", 1" |
| Sealing method | Washer or O-ring | Thread tape or pipe dope |
| Threads per inch | 11.5 TPI | 14 TPI (for 3/4" NPT) |
| Typical use | Garden hoses, spigots, sprinklers | Indoor plumbing, gas lines |
The most important difference is how each type creates a seal. GHT fittings rely on a rubber washer or O-ring seated inside the female coupling. The washer compresses against the face of the male fitting when tightened. NPT fittings seal through the interference of the tapered threads themselves, often aided by thread sealant tape (Teflon tape) or pipe dope.
Because these two thread types are incompatible, adapter fittings are widely available. The most common adapter converts 3/4" GHT to 1/2" NPT, which lets you connect a garden hose to standard household plumbing. Adapters also come in 3/4" GHT to 3/4" NPT configurations. Understanding these distinctions is part of good plumbing maintenance for your home.
Garden hose interior diameters
Garden hoses are manufactured in four standard interior diameters: 3/8 inch, 1/2 inch, 5/8 inch, and 3/4 inch. The interior diameter directly affects water flow rate and pressure. While the fittings on each end are all the same standard GHT size, choosing the right diameter depends on your intended use.
| Interior Diameter | Water Flow (Approx.) | Best For |
|---|---|---|
| 3/8" | 2 – 4 GPM | Light watering, small containers, RV use |
| 1/2" | 4 – 6 GPM | General gardening, light-duty tasks |
| 5/8" | 7 – 10 GPM | Most residential use (most popular size) |
| 3/4" | 10 – 15 GPM | Heavy-duty watering, commercial applications, long runs |
The most popular size
The 5/8-inch interior diameter is by far the most common choice for homeowners. It provides a strong balance of water flow and manageable weight. Most garden hoses sold at hardware stores and home centers default to this size.
When to choose 3/4 inch
A 3/4-inch hose delivers significantly more water volume, making it ideal for filling large pools, running multiple sprinklers on a long line, or handling commercial landscaping tasks. The tradeoff is a heavier, bulkier hose that's harder to maneuver in tight garden spaces.
Lightweight options
Hoses with 3/8-inch and 1/2-inch diameters are lighter and easier to coil. They work well for balcony gardens, potted plants, washing a car, or connecting to an RV water hookup. However, their reduced flow makes them impractical for watering large lawns or running sprinkler systems.
Parts of a garden hose coupling
A standard garden hose has three main coupling components: two ferrules, one male fitting, and one female fitting. Understanding these parts helps when replacing a damaged connector or choosing replacement components.
| Component | Location | Function |
|---|---|---|
| Ferrule | Both ends (over the hose) | Secures the fitting to the hose body |
| Male coupling | One end of the hose | Screws into a female fitting (nozzle, sprinkler, another hose) |
| Female coupling | Other end of the hose | Screws onto a male fitting (spigot, faucet) |
| Washer/O-ring | Inside the female coupling | Creates a watertight seal |
The ferrule
A ferrule is a cylindrical sleeve that wraps around the outside of the hose at each end. It holds the hose tightly against the inserted fitting. Ferrules come in two styles: ribbed ferrules work with internally expanded fittings, while smooth ferrules pair with barbed fittings that are crimped into place using a die.
The male coupling
The male coupling features external threads and a tail (also called a stem) that inserts into one end of the hose. The threaded portion screws into the female coupling of a nozzle, sprinkler, or another hose. Male couplings come in one-piece or two-piece designs, with tails that are either barbed or designed for expansion.
The female coupling
The female coupling has internal threads housed inside a rotating collar and a tail that inserts into the opposite end of the hose. This end connects to the spigot or faucet. A rubber washer or O-ring sits inside the female coupling to create the watertight seal.
Garden hose couplings do not seal through thread contact. The seal is created by the washer compressing against the mating surface. Over-tightening can crush or deform the washer, causing leaks rather than preventing them. Hand-tight plus a quarter turn is usually sufficient.
Garden hose fitting materials
Garden hose fittings are made from several different materials, each with distinct advantages in durability, weight, and cost. Brass was once the universal standard, but regulations and rising material costs have introduced alternatives.
| Material | Durability | Weight | Price Range |
|---|---|---|---|
| Brass | Excellent; corrosion-resistant | Heavy | $5 – $15 per fitting |
| Aluminum | Good; lighter than brass | Medium | $3 – $10 per fitting |
| Stainless steel | Excellent; very corrosion-resistant | Heavy | $8 – $20 per fitting |
| Plastic (ABS/nylon) | Fair; prone to cracking over time | Light | $1 – $5 per fitting |
| Zinc-coated steel | Good; can rust if coating wears | Heavy | $3 – $8 per fitting |
Brass remains the preferred choice for quality garden hose fittings because it resists corrosion, handles temperature changes well, and lasts for many years. Regulations like California's Proposition 65 initially raised concerns about lead content in brass, but the lead levels in brass hose fittings fall well below regulated thresholds.
Plastic fittings are the most affordable option and reduce hose weight, but they can crack in cold weather, strip when over-tightened, and degrade under UV exposure. For a hose that will see heavy use, brass or stainless steel fittings are worth the investment.
Common garden hose adapters
When you need to connect a garden hose to plumbing, appliances, or non-standard equipment, adapters bridge the gap between GHT and other thread types. These small brass or plastic fittings are inexpensive and widely available at hardware stores.
| Adapter Type | Converts From | Converts To | Typical Price |
|---|---|---|---|
| GHT to NPT | 3/4" GHT | 1/2" NPT | $5 – $10 |
| GHT to NPT (3/4") | 3/4" GHT | 3/4" NPT | $5 – $12 |
| Hose mender/splice | GHT male | GHT male | $3 – $8 |
| Double female | GHT female | GHT female | $3 – $8 |
| Quick connect | GHT | Snap-on coupling | $8 – $15 per set |
| Y-splitter | 1 GHT female | 2 GHT male outlets | $8 – $20 |
GHT to NPT adapters
The most frequently purchased adapter converts 3/4" GHT to 1/2" NPT. This allows you to connect a garden hose to indoor plumbing fixtures, laundry hookups, or irrigation systems with pipe threads. These adapters come in male-to-male, female-to-female, and male-to-female configurations to match whatever connection you need.
Quick-connect fittings
Quick-connect systems let you snap a hose on and off a faucet or accessory without twisting. A male quick-connect base stays attached to the spigot, while a female quick-connect coupling stays on the hose. Pressing the coupling onto the base creates an instant, leak-free connection. These systems are especially popular for gardeners who frequently swap between nozzles, sprinklers, and other attachments.
How to measure a garden hose fitting
If you have an unknown fitting and need to identify its size, you can measure it with a ruler, caliper, or thread gauge. The key measurements are the outer diameter of the male threads and the number of threads per inch (TPI). Knowing how to read a tape measure accurately will help with this process.
| Step | What to Do | Standard GHT Result |
|---|---|---|
| 1. Measure outer diameter | Measure across the widest point of the male threads | Approximately 1-1/16" (1.0625") |
| 2. Count threads per inch | Count how many thread peaks fit in one inch | 11.5 TPI |
| 3. Check thread profile | GHT threads are straight/parallel; NPT threads are tapered | Straight (parallel) |
To count threads per inch, place a ruler along the threaded section and count how many complete thread ridges span one inch. For GHT fittings, you should count 11.5 threads per inch. If you count 14 TPI and the threads appear to taper, you likely have an NPT fitting instead.
A thread pitch gauge is the most accurate tool for identification. These inexpensive gauges have multiple blades with different thread profiles. Simply press each blade against the threads until one matches perfectly. Hardware stores often have gauges available for customer use.
Measuring hose interior diameter
To determine your hose's interior diameter, look at the cut end of the hose and measure across the inside opening. Do not measure the outside of the hose, as wall thickness varies between manufacturers and materials. Most hoses also have the diameter printed on the surface or listed on the product packaging.
Frequently asked questions
Are all garden hose fittings the same size?
In the United States and Canada, yes. Nearly all residential garden hose fittings use the standard 3/4"-11.5 GHT thread size. This means any standard garden hose will connect to any standard outdoor faucet, nozzle, or sprinkler. Some specialty or industrial hoses may use different thread sizes, but these are uncommon for home use.
Can I connect a garden hose to a pipe thread fitting?
Not directly. GHT (garden hose thread) and NPT (national pipe thread) are incompatible because GHT threads are straight while NPT threads are tapered. You need a GHT-to-NPT adapter, which typically costs $5 to $12 and is available at any hardware store.
Why does my garden hose fitting leak?
The most common cause is a worn, missing, or damaged rubber washer inside the female coupling. Garden hose connections seal through washer compression, not thread contact. Replacing the washer (a pack usually costs under $3) fixes most leaks. Over-tightening can also crush the washer and cause leaks.
Does hose diameter affect the fitting size?
No. The interior diameter of the hose (3/8", 1/2", 5/8", or 3/4") determines water flow volume, but the threaded coupling on each end is the same 3/4"-11.5 GHT standard regardless of hose diameter. The tail (stem) portion that inserts into the hose is sized differently to match each diameter, but the threaded end remains universal.
What is the best material for garden hose fittings?
Brass is widely considered the best material for garden hose fittings due to its corrosion resistance, durability, and longevity. Stainless steel is an excellent alternative that offers even greater corrosion resistance. Plastic fittings are lightweight and inexpensive but tend to crack or strip with heavy use.
Do European garden hoses use the same fitting size?
No. European garden hoses typically use metric BSP (British Standard Pipe) threads rather than GHT. Common European sizes include 3/4" BSP and 1/2" BSP, which have different thread pitches than American GHT fittings. If you need to connect American and European equipment, you will need a GHT-to-BSP adapter.