The golden rule of rod length
The industry standard is to add 2 to 3 inches to each side of your runner width. This ensures the brackets mount securely onto the tread rather than the riser, providing a stable, elegant look that frames your runner correctly.
How much runner do I need?
Working with a 13-step flight (10 in / 25 cm treads, 7.5 in / 19 cm risers), you require 23.5 ft (7.09 m) of runner, including waste. When measuring for rods, always measure the runner width first, then add the recommended 4-6 inches total for your rod length.
| Measurement | US (in/ft) | UK (cm/m) |
|---|---|---|
| Runner width | 27 in | 68.5 cm |
| Extra length per side | 2-3 in | 5-7.5 cm |
| Total rod length | 31-33 in | 78.5-83.5 cm |
| Total (13 steps) | 19.77 ft | 5.97 m |
| With 8% waste | 23.5 ft | 7.09 m |
Know your numbers in 30 seconds
Enter your step count, tread depth and riser height — the stair runner calculator gives you the exact length to order, in metres and feet, with waste included.
Open the stair runner calculatorPro tip
Always check if your finials fit within the space available at the edge of the stair tread.
- Measure your runner width accurately
- Add 2-3 inches per side
- Check for clearance at the wall
- Standardize your rod length for all steps
Whatever you decide, get the numbers first: the stair runner calculator doubles as a stair runner length calculator, adding nosing wrap, landings, winders, pattern repeat and waste so you order the right length the first time.
Still deciding on material, width or pattern? Our hub on stair runners compares weaves, widths, backings and fitting styles side by side, then hands the numbers straight to the calculator.
Frequently asked questions
Should all stair rods be the same length?
Yes, for a consistent look on a straight flight, every rod should be exactly the same length.
What if my stairs are different widths?
If your staircase narrows or widens, you will need to measure each step individually and order custom lengths accordingly.
Does the finial count towards the rod length?
Usually, the rod length refers to the tube length between the finials, but confirm this with your supplier when ordering.
What happens if the rods are too long?
If they are too long, they may extend beyond the tread and interfere with wall trim or skirting boards.
Can I use rods on open-sided stairs?
Yes, but you will need specialized bracket hardware designed for open-sided stair treads.
How do I measure carpet width?
Measure the width of the runner itself at the point where the rods will be placed.
Are rods sold in pairs?
They are typically sold per step, so you will need to order one for each step of your staircase.
What if I have winders?
Winder stairs require custom lengths for each step because the shape of the tread is irregular.
Know your numbers in 30 seconds
Enter your step count, tread depth and riser height — the stair runner calculator gives you the exact length to order, in metres and feet, with waste included.
Size your staircase and rod lengths with our calculatorEvery guide is written from hands-on measuring and fitting experience, checked against the calculator’s own maths, and re-reviewed whenever prices or methods change. Read our editorial standards.