Sampo Lightingtrack rail
Calculator · one run, counted per leg

Track rail calculator: rails, joiners, feeds and caps for one run

Choose a layout, type the length of each leg in metres, then pick a wire system, the stock rail length you're assuming and how the rail mounts. The planner counts every leg separately, adds the legs up and prints a parts list you can carry straight into an enquiry. Nothing here is a price or a stock promise — it's the arithmetic, shown in full.

Rail parts planner

one continuous run · counted per leg
Layout
Straight uses leg 1; L uses legs 1–2; U uses legs 1–3; rectangle (closed loop) uses legs 1–4.
Leg lengths in metres
One field per leg, measured corner to corner or corner to open end.
Wire system
Heads must match the rail wire system and voltage — confirm at enquiry.
Stock rail length
Assumed stock length — confirm per model.
Fixing spacing is per model and ceiling — confirm.

The parts list appears here as you type. Without JavaScript, the count rules below give the same numbers by hand.

Count rules — the same arithmetic the planner runs
LineHow it is counted
RailsFor each leg, divide the leg length by the assumed stock length and round up. Then add the legs together. Never divide the whole run in one go: a rail can't turn a corner.
Straight joinersFor each leg, the rails in that leg minus one. Then add the legs together.
Corner joinersStraight run 0, L-shape 1, U-shape 2, rectangle 4.
Power feeds1 per run. A rectangle is a closed loop; long loops may need a second feed point — confirm.
End caps2 on an open run (straight, L or U); 0 on a closed rectangle.
MountingNamed as chosen: surface, recessed or suspended. Fixing spacing is per model and ceiling — confirm.

Worked example. L-shape, leg 1 = 4.5 m, leg 2 = 3.2 m, assumed stock length 2.0 m. Leg 1: 4.5 ÷ 2.0 = 2.25, round up to 3 rails and 2 straight joiners. Leg 2: 3.2 ÷ 2.0 = 1.6, round up to 2 rails and 1 straight joiner. Totals: 5 rails, 3 straight joiners, 1 corner joiner, 1 power feed, 2 end caps. Dividing the whole 7.7 m at once gives 4 rails — one short, because no rail bends round the corner.

Worked examples

Three layouts, worked by hand, so you can check the planner against your own pencil. Each uses an assumed stock length — confirm per model before ordering.

Straight run

Straight run, leg 1 = 7.0 m, stock length 3.0 m. 7.0 ÷ 3.0 = 2.33, round up to 3 rails and 2 straight joiners. Totals: 3 rails, 2 straight joiners, 0 corner joiners, 1 power feed, 2 end caps.

U-shape

U-shape, leg 1 = 2.5 m, leg 2 = 4.0 m, leg 3 = 2.5 m, stock length 2.0 m. Leg 1: 1.25, round up to 2 rails, 1 joiner. Leg 2: exactly 2 rails, 1 joiner. Leg 3: 2 rails, 1 joiner. Totals: 6 rails, 3 straight joiners, 2 corner joiners, 1 power feed, 2 end caps.

Rectangle

Rectangle, leg 1 = 4.0 m, leg 2 = 3.0 m, leg 3 = 4.0 m, leg 4 = 3.0 m, stock length 1.5 m. The 4.0 m legs: 2.67, round up to 3 rails, 2 joiners each. The 3.0 m legs: exactly 2 rails, 1 joiner each. Totals: 10 rails, 6 straight joiners, 4 corner joiners, 1 power feed (a second may be needed — confirm), 0 end caps.

What changes the count

Four things move the numbers, and only one of them is the length of the run.

  • The stock length you assume. A shorter stock rail means more rails and more straight joiners for the same leg. Try the same layout at 1.0 m and 3.0 m and you'll see the joiner line swing more than the rail line.
  • Where the corners fall. Every corner starts a new leg, and each leg is rounded up on its own. That's why an L-shape usually needs more rails than a straight run of the same total length.
  • Legs on an exact multiple. A 4.0 m leg at an assumed 2.0 m stock is exactly 2 rails with 1 joiner. Add a few centimetres and it becomes 3 rails with 2 joiners, so measure the finished leg, not the room.
  • The ceiling. A beam, a duct or a change of ceiling type can force a run to turn, which splits a leg in two and adds a corner joiner. Re-run the planner whenever the layout changes on site.

A rail cut on site still counts as one rail here. Whether a given rail can be cut, and how the cut end is finished, is a per-model question we'll answer with the list.

What to confirm before ordering

The list is a count, not a specification. Send it and we'll come back on each of these for the system you selected:

  1. The actual rail lengths available in your chosen wire system, replacing the assumed stock length.
  2. Finish and colour of rail, joiners, caps and feed so they match on the ceiling.
  3. Feed type and position, and whether a long run or closed loop needs a second feed point.
  4. Which switching, grouping or dimming arrangement the exact system supports — never inferred from the wire count.
  5. That every track head on the run matches the rail wire system and voltage.
  6. Fixing spacing and mounting parts for your ceiling, per model.
  7. Certifications for the models chosen — per model, check the spec sheet.

Carry the result into your enquiry

The send button above copies the list and opens the contact form with the list already in the message box. Edit it, add drawings or photos, and we'll confirm the parts for that system.