Pressure Washer Nozzles: Specs and Selection Made Easy
Any time you search the web for pressure washer fittings, you get hit with a wave of confusing jargon, inconsistent terms, and too many options. Even on Obsessed Garage, it can be a lot to process. If you're stuck trying to make sense of it all, this guide will help.
We’ve tested more than 70 pressure washers to take out the guesswork and find the best nozzle sizes for each machine.
Check that out here: The Pressure Washer Project
Nozzle Specifications
There are three things to pay attention to when looking at a nozzle:
- Fan Spread – measured in degrees (0°, 15°, 25°, 40°)
- Orifice Size – shown as a number (like 4.0, 2.0, 6.0)
- Connection Type – either threaded or 1/4" quick disconnect (QD) plug
Example:
You can have multiple fan spreads in the same orifice size:
- 0°, 15°, 25°, and 40° in a 4.0 size
- Or in 2.0, 6.0, etc.
Stamped Example: A nozzle marked 2504 means:
- 25° fan pattern
- 04 (4.0) orifice size
Most nozzles use a 1/4" plug that snaps into your wand or sprayer. Some older or specialty nozzles use 1/8" male NPT threads and screw directly into the wand.
Nozzle Selection: What Matters Most
The most important number to look at is GPM (gallons per minute)—not PSI.
Here’s why:
- A pressure washer doesn’t “build pressure” on its own
- The nozzle creates the pressure by restricting water flow
That means the nozzle controls how your machine performs:
- Too big = weak pressure
- Too small = too much pressure, reduced flow
Our goal for vehicle washing:
1000–1200 PSI with the highest flow possible
This keeps surfaces safe while still getting them clean.
Choosing the Right Nozzle Size
Use your machine’s GPM rating and cross-reference with your ideal PSI to find the right nozzle.
This chart (based on MTM Hydro’s calculator) is a great starting point. But don’t treat it as the final word. Sometimes a slightly larger or smaller nozzle performs better depending on the specific machine.
Pro Tip: Never use a nozzle that puts your machine over its rated working PSI.