Curtain heading tape calculator
Heading tape is sewn across the flat width of the finished curtain, so the length needed is the cloth in the made-up curtain — the widths bought, less the side hems and the seams at every join — plus a turnback folded under at each end. Hooks are a different measurement entirely: they sit along the curtain once it is gathered, not along the flat tape, which is why counting them on the tape length buys roughly two and a half times too many.
Your curtains
Turnbacks, hems and hook spacing
5.3 m
530 cm of tape across 2 curtains. Rounded up to nearest 10 cm.
- Flat width of each curtain
- 261 cm2 widths, less hems and joins
- Tape per curtain
- 265 cmplus 4 cm turned under
- Hooks
- 2814 per curtain at 8 cm spacing
- Cord in the tape
- 1590 cmthree cords, drawn from one end
Tape is sold by the metre from a roll, or in packs. Round up to whatever your shop sells — the surplus is the cheapest insurance on the job, and a tape join in the middle of a curtain heading is visible for the life of the curtain.
How we got this
- Tape per curtain — 265 cm261 cm of flat curtain + 4 cm turned under at the ends
- Tape in total — 530 cm265 cm × 2 curtains
- Hooks per curtain — 14 hooks100 cm of gathered curtain ÷ 8 cm spacing, plus one to finish the run
How this calculator works
Heading tape is sewn across the top of the curtain before it is gathered, so its length is the flat width of the made-up curtain — not the track width, and not the width of the window. That flat width is the widths of cloth you bought, less the two side hems and less two seam allowances at every join, which is exactly the figure the fullness calculator produces. This tool calls that same function rather than working it out again.
Add a turnback at each end — 2 cm is normal, folded under so no raw tape edge shows at the leading edge — and multiply by the number of curtains. That is the whole tape calculation.
Hooks are not measured on the tape
This is the mistake worth the page. The tape is flat when you buy it and gathered when the curtain hangs, and the hooks live in the gathered version. They sit along the span the curtain actually covers, spaced every 8 cm or so, and that span is much shorter than the tape they are pushed into.
On the worked example below, each curtain carries 261 cm of flat cloth but covers only half a 200 cm track once hung. Counting hooks along the tape gives 34 per curtain. Counting them along the gathered curtain — which is what the calculator does — gives 14. Buying the first number is buying 2.4 times as many hooks as the curtain has room for.
A worked example
A 200 cm track, a pair of pencil-pleat curtains at 2.5× fullness in 140 cm fabric. These are the calculator's own starting values, so the table below is the arithmetic the tool runs rather than a retelling of it.
| Step | Working | Result |
|---|---|---|
| Tape per curtain | 261 cm of flat curtain + 4 cm turned under at the ends | 265 cm |
| Tape in total | 265 cm × 2 curtains | 530 cm |
| Hooks per curtain | 100 cm of gathered curtain ÷ 8 cm spacing, plus one to finish the run | 14 hooks |
Tape by heading style
Every row below is the same 200 cm track and the same 140 cm cloth, each heading at its own recommended fullness.
| Heading | Fullness | Tape in total | Hooks | Corded? |
|---|---|---|---|---|
| Pencil pleat | 2.5× | 530 cm | 28 | Yes |
| Pinch pleat | 2.2× | 530 cm | 28 | No |
| Eyelet | 2.0× | 530 cm | 28 | No |
| Tab top | 1.8× | 530 cm | 28 | No |
| Wave | 2.2× | 530 cm | 28 | Yes |
Two things fall out of that table. Tape length follows fullness and nothing else — two headings made to the same fullness take the same tape however different they look on the pole. And the hook count barely moves at all, because it depends on the gathered span, which is the track either way. What each heading actually is, and why it needs the fullness it needs, is set out on curtain heading types.
Eyelet and tab-top headings appear in the table for completeness, but they carry no tape at all: the fixing is built into the curtain. An eyelet is a ring punched through a stiffened band and a tab is a loop of the same cloth, and neither takes hooks either.
How to measure for this
- Measure the track. The pole or track the curtains hang from, finials excluded. Tape is worked out from the curtains, but the track is where the curtains come from.
- Take the fabric width. The roll width the curtains are made from, as sold. The tape length follows from how many widths each curtain takes.
- Set the fullness. The same figure the curtains were made to. More fullness means more flat cloth, and the tape runs across all of it.
- Choose the hook spacing. Along the finished, gathered curtain. 8 cm is usual; closer spacing holds a heavy fabric better.
- Add the turnbacks. A couple of centimetres folded under at each end of each curtain, so no raw tape edge is left showing.
What this assumes
- Tape is bought by the metre from a roll. If yours comes in packs, round up to a whole pack — a tape join in the middle of a curtain heading is visible for the life of the curtain.
- One tape across the full flat width. Tape is not cut back at the leading edge or the return; the turnbacks enclose the ends instead.
- Hook spacing is a choice, not a property of the tape. Pencil-pleat tape has pockets far closer together than any hook spacing you would use; 8 cm is the usual pick and a heavier fabric wants closer.
- Cord is not bought separately. It comes in a corded tape. The figure shown is what is inside, which is useful when you are pulling the cords and wondering how much slack to expect.
- Rounding is always up, as everywhere on this site.
For the cloth itself, the curtain fabric calculator takes the fullness, the heading allowance and the pattern repeat together, and the curtain lining calculator does the lining on its own narrower roll.
Common questions
- How much heading tape do I need for a pair of curtains?
- The flat width of both finished curtains, plus a turnback at each end. For a pair made from two widths of 140 cm fabric each, that is a little over 5 metres. It is the flat cloth that matters, not the track width — the tape is sewn on before the curtain is gathered.
- How many curtain hooks do I need?
- Count them along the gathered curtain, not along the tape. A pair on a 200 cm track covers 100 cm each once hung, so at 8 cm spacing that is about fourteen hooks per curtain. Counting on the flat tape instead would suggest thirty-four, which is where most over-ordering comes from.
- Do eyelet or tab-top curtains need heading tape?
- No. Both have their fixing built into the curtain — an eyelet is a metal ring punched through a stiffened band, a tab is a loop of the same cloth passed over the pole. Neither takes tape and neither takes hooks. A lightweight stiffener behind the band is a separate thing from heading tape.
- Can I use any heading tape on any track?
- Almost, with one exception. Wave tape holds a fixed cord spacing that only a wave track is built to carry; on an ordinary track the folds collapse into an uneven gather and the effect is lost. Pencil pleat, pinch pleat and standard tapes all work on a normal track or pole.
- How much cord is in a heading tape?
- Three cords run the length of a corded tape and are drawn from one end to gather it, so the cord in the tape is roughly three times its length. You do not buy that separately — it comes in the tape — but it is worth knowing when you are pulling the cords up and wondering how much slack to expect.
Related tools
Curtain fullness calculator
How many widths each curtain needs at the fullness you want — and what whole widths really gather to.
Curtain fabric calculator
Track width, drop, fullness and pattern repeat in; metres or yards to buy out, with every allowance adjustable.
Curtain heading types
Five headings compared on fullness, allowance and what they cost in cloth.
Curtain lining calculator
Lining on its own narrower roll, from the flat width your curtains already need.