NAIL GUN GAUGES EXPLAINED: WHAT SIZES ARE BETTER FOR DIFFERENT JOBS

When it comes to nailing like a pro, understanding nail gun gauge is key to choosing the right nail gun for your work. The gauge determines how thick the nail is, which in turn affects how strong the hold will be and how visible the nail head will look after firing. 

Commonly used nails include 15-gauge, 16-gauge, 18-gauge, 21-gauge, and 23-gauge. Perhaps counterintuitively, the higher a gauge number, the thinner a nail's thickness, meaning a 16-gauge nail is thicker than a 23-gauge one.

Nails of certain gauges also go by different names; one of the major differences between brad nails and finish nails is their typical gauges Let’s break down the common nail gauge and see what they’re best suited for.

15-Gauge Nails: For Heavy-Duty Finish Work

Best for:

• Interior and exterior trim
• Baseboards and crown molding
• Door and window casings
• Cabinets and stair treads

Nailers: Angled finish nailers

These nails are thick, strong, and hold well in hardwoods. They're typically collated at an angle, making them easier to maneuver in tight spots. If you're installing trim or working on structural pieces that need to stay put, 15-gauge is your go-to.

16-Gauge Nails: The All-Rounder

Best for:

• Finish carpentry
• Paneling
• Light trim work
• Shelving and baseboards

Nailers: Straight or angled finish nailers

A bit thinner than 15-gauge but still strong, 16-gauge nails offer a balance between holding power and subtle appearance. These are often used for medium-duty trim work where a slightly smaller nail hole is preferred.

18-Gauge Nails: The Brad Nailer Standard

Best for:

• Small trim pieces
• Decorative molding
• Picture frames
• Panel attachments
• Shoe molding

Nailers: Brad nailers

Brad nails are thin and almost invisible after installation, making them ideal for delicate trim and detailed work. However, they don’t have the same holding strength as 15- or 16-gauge nails, so they’re not ideal for anything structural.

21-Gauge Nails: Micro-Pins with Slight Grip

Best for:

• Ultra-fine finish work
• Pre-finished moldings
• Light paneling
• Temporary hold before glue dries

Nailers: Micro pin nailers

Though not as common as other gauges, 21-gauge nails offer a midpoint between 18- and 23-gauge. They provide slightly more holding strength than a 23-gauge pin without sacrificing finesse. Great for light decorative trim where appearance matters.

23-Gauge Nails: Nearly Invisible Pinning

Best for:

• Delicate trim
• Veneers and inlays
• Cabinet face frames
• Temporary tack before gluing

Nailers: Pin nailers

These are the smallest and least obtrusive nails you can shoot with a nail gun. Ideal for detail work and thin materials, 23-gauge pins often don’t even require wood filler afterward. Just remember, they offer minimal holding power—glue is usually needed to reinforce the bond.

Choosing the Right Nail Gun Gauge
Think of nail gauge like choosing the right size screw: bigger isn’t always better. The right gauge depends on your project”s size, the materials involved, and the desired finish. Here's a quick reference.

       
Before you load up a nailer, consider the gauge and the job at hand. It’s the difference between a flawless finish and a frustrating redo. Want to dive deeper into specific nail gun types? Stay tuned for our another guide on Finish Nailer vs. Brad Nailer: Which One is right for your project?