Roofing Nails Calculator
Reviewed by the My Roof Pitch editorial team · Updated · Free, no sign-up, works offline after first load
A standard four-nail pattern uses about 320 nails per square, or just over 2 pounds. A six-nail high-wind pattern uses about 480 nails per square, or roughly 3 pounds. For a 20-square roof that is 6,400 to 9,600 nails.
Your measurements
Enter the values you know — results update live.
True sloped roof area in square feet.
Choose the nailing pattern required by the shingle warranty or wind zone.
Standard 1.25-inch roofing nails are about 160 per pound.
Analysis
Live results from your measurements.
Show the working
- Squares:
2,000 ÷ 100= 20 - Field nails:
20 × 4 × 80= 6400 - Pounds:
6400 ÷ 160= 40 lb - Boxes:
40 ÷ 50= 0.8 - Underlayment fasteners:
2,000 × 0.1= 200
What this calculator does
Roofing nails are the least glamorous line item on a roof, but running out halfway through a course is expensive. The count is driven by the nailing pattern specified by the shingle manufacturer and the local wind code. A standard four-nail pattern puts four fasteners per shingle, and because there are roughly 80 shingles per square, that works out to about 320 nails per square. High-wind zones require six nails per shingle, which pushes the count to about 480 per square. Nails are sold by weight, and a standard 1.25-inch coil roofing nail has about 160 nails per pound. Underlayment is often fastened with staples or cap nails at roughly one fastener every 10 square feet.
How to use it
- Enter the true sloped roof area in square feet.
- Select the nailing pattern: 4-nail standard, 5-nail wind, or 6-nail high-wind.
- Confirm nails per pound from the nail packaging or supplier.
- Add underlayment fasteners if you are fastening the underlayment separately.
- Round up to the next box or pound when ordering.
The formula
Field nail count
nails = (roof area / 100) × pattern × 80
80 shingles per square times the number of nails per shingle.
Pounds of nails
pounds = nail count / nails per pound
Standard coil roofing nails are about 160 per pound.
Underlayment fasteners
fasteners = roof area × fasteners per sq ft
Typical underlayment fastening is one staple or cap nail per 10 sq ft.
Worked example
A 2,400 sq ft roof with a six-nail high-wind pattern and 160 nails per pound.
- Squares: 2,400 ÷ 100 = 24
- Nails: 24 × 6 × 80 = 11,520
- Pounds: 11,520 ÷ 160 = 72 lb
- Boxes: 72 ÷ 50 = 1.44
Order 2 boxes of nails, or about 75 pounds, for the field shingles.
Reference chart
| Pattern | Nails per square | Pounds per square (160/lb) | Pounds per square (120/lb) |
|---|---|---|---|
| 4-nail | 320 | 2 | 2.7 |
| 5-nail | 400 | 2.5 | 3.3 |
| 6-nail | 480 | 3 | 4 |
| 8-nail | 640 | 4 | 5.3 |
Nail type by roofing material
| Material | Nail type | Length | Notes |
|---|---|---|---|
| Asphalt shingles | 11-gauge coil | 1.25 in | Hot-dip galvanized. |
| Wood shingles | Stainless or hot-dip | 1.5 in | Two per shingle typical. |
| Wood shakes | Hot-dip or stainless | 1.75–2 in | Often with shims. |
| Underlayment | Cap nail or staple | 1 in | Plastic or metal caps prevent tear-out. |
Common mistakes
- Using too few nails in high-wind zones and voiding the shingle warranty.
- Buying nails by the pound without checking the count per pound.
- Forgetting starter course and ridge cap nails, which are in addition to field nails.
- Using non-galvanized nails that rust and stain the roof.
- Ignoring underlayment fasteners, which are a separate quantity.
Assumptions and limits
- Standard asphalt shingle coverage of roughly 80 shingles per square.
- Nail count does not include starter strip, ridge cap or flashing fasteners.
- Nails per pound is based on the specific nail size and supplier.
- Underlayment fasteners are optional and entered separately.
Frequently asked questions
How many roofing nails per square?
About 320 nails per square for a four-nail pattern, or 480 for a six-nail high-wind pattern.
How many pounds of roofing nails per square?
Roughly 2 pounds per square for a four-nail pattern using standard 1.25-inch coil nails at 160 per pound. Six-nail patterns need about 3 pounds per square.
What size roofing nails for shingles?
Standard asphalt shingles use 12-gauge or 11-gauge hot-dip galvanized roofing nails, 1.25 to 1.5 inches long, with a 3/8 inch head.
How many nails per shingle?
Standard installation uses four nails. High-wind and steep-slope installations require six nails per shingle.
Can I use staples for shingles?
Most shingle manufacturers and building codes no longer allow staples for asphalt shingles because they pull through under wind load. Use approved roofing nails.
How many boxes of roofing nails should I order?
A standard box holds 50 pounds. For a 20-square roof with a four-nail pattern, order one box. For a six-nail pattern or a 30-square roof, order two boxes to be safe.
Related guides
Last updated 2026-08-05. Results are estimates for planning and are not a substitute for a licensed engineer or local code review.