Measure stairs, runners, and landings with practical accuracy. Review waste, roll usage, and fitted pricing. Plan purchases confidently before cutting, ordering, and booking installers.
| Scenario | Stairs | Coverage | Width | Landings | Waste | Estimated Area |
|---|---|---|---|---|---|---|
| Runner on standard stairs | 14 | Runner | 30 in | 1 at 42 × 42 in | 10% | 56.25 sq ft |
| Full coverage, no landing | 12 | Full | 40 in | 0 | 8% | 61.33 sq ft |
| Wide runner with pattern match | 16 | Runner | 32 in | 2 at 48 × 48 in | 12% | 89.78 sq ft |
1. Per stair run length
Per stair run = tread depth + riser height + nosing allowance
2. Stair carpet area
Stair area = number of stairs × per stair run × coverage width
3. Landing area
Landing area = landing count × landing length × landing width
4. Purchase area
Purchase area = (stair area + landing area) × (1 + waste%) × (1 + pattern%)
5. Roll length
Required roll length = purchase area ÷ carpet roll width
6. Final cost
Total = carpet cost + underlay cost + installation + extras + tax
Rounded roll length moves to the next half unit for safer ordering.
Yes. Choose runner for a centered stair runner or full for wall-to-wall coverage across each stair width.
Carpet wraps over the stair edge. Nosing allowance adds material for that bend, helping estimates better match real installation needs.
Waste covers trimming, fitting, and minor errors. Pattern allowance covers extra material needed to align visible repeats or directional carpet designs.
Carpet is often bought in practical lengths. Rounding upward avoids under-ordering and gives a safer estimate for cuts and fitting adjustments.
Yes. Enter the number of landings plus each landing length and width. Their area is added to the main stair carpet requirement.
Use per step when installers charge by stair. Use per area when pricing is based on total carpet coverage instead.
No. It provides a strong planning estimate. Final orders should still be verified with actual site measurements and installer requirements.
Yes. Switch to metric mode and enter stair dimensions in centimeters. Results are then shown in meters and square meters.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.