What Are the Standard Thread Sizes Used in Faucet Aerators?

Question

I was thinking of attaching a sink spray hose to my faucet's (male) aerator threads, but I am not sure if I need a fitting for it or not. I've tried looking online to see what the standard sizes for faucet aerators are, but I keep getting different answers. Can I have a list of the sizes (In NPT) if I'm using a male-threaded bathroom faucet?

Answer 1

There are many sizes of faucet aerator threads. You can get an idea from the picture of the thread gauge below that you will typically see at a better equipped hardware store where aerator units are sold. (In my experience typical for a USA hardware store. Your situation may vary depending upon your geographical region).

The thread gauge above supports the following thread sizes:

1/4-18 (M)

1/4-18 (F)

3/8-18 (M)

3/8-18 (F)

1/2-27 (F)

1/2-IPS (F)

9/16-24 (M)

5/8-18 (M)

5/8-24 (M)

5/8-27 (M)

11/16-24 (M)

11/16-27 (M)

3/4-11 (F)

3/4-27 (F)

13/16-20 (M)

13/16-24 (M)

13/16-24 (F)

55/64-27 (F)

15/16-24 (M)

15/16-27 (M)

*(F) Denotes stud used to determine female thread size

*(M) Denotes tapped hole used to determine male thread size

Add in metric sizes from other parts of the world and this list is likely to grow considerably.

Answer 2

What are the standard thread sizes used in [tap] aerators?

M20, M22, M24 and M28.

Note that of the 193 nations recognised by the UN, there are still one or two† that still cling to non-standard sizes based on the size of their current or some previous king's thumb or something similar.

You can't mix them. For example don't try to mate a standard sized aerator with your 37/59ths-17¾(T) widdershins faucet. You might get them to connect using your large adjustable nut-rounder and heavy thumb-detector but subsequent removal may require the angle-grinder.

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† Myanmar, Liberia and some other such place.