Curtain Size Lab Search

HARDWARE GUIDE · REVIEWED SEPTEMBER 11, 2026

Curtain Rod Sizes: Working Length and Overall Span

Size a curtain rod from window width, side extension, stack-back, and finial allowance without making fixing or load claims.

MEASURED WIDTHFINISHED DROP
Original proportional diagram. Use actual measurements; drawing is not to scale for a specific product.

SHORT ANSWER

Start here

Curtain rod working length is the span available to the panels, normally excluding finials. If no rod is installed, window width plus adjustable side extension is a planning estimate; keep finial allowance and stack-back separate, then verify the exact hardware range and instructions.

Working rodExclude finials
Common side example6 in / 15 cm
Overall spanRod + both finials
FixingsFollow manufacturer

How to measure

  1. 01

    Measure the actual working rod or track width; if hardware is not installed, record the window-frame width and your planned side extensions separately.

  2. 02

    Measure the drop from the reference point stated for the selected heading—not from an unrelated edge of the window.

  3. 03

    Check whether a package contains one panel or a pair, then compare total flat fabric width rather than the label width alone.

  4. 04

    Recheck the selected product, tape, hooks, carriers, and fabric before ordering or cutting.

WORKED CALCULATION

Working-rod example

Window-frame width
60 in (152.4 cm)
Side extension
6 in each side
Finials
Measured separately
Formula60 in + 6 in + 6 in

72 in (182.9 cm) planned working rod length

Confirm the selected product range, returns, finial span, support, and capacity separately. This is not installation guidance.

Recalculate with your measurements

Working length versus decorative span

A product may list an adjustable rod range while the finials add extra wall-to-wall space. The calculator reports both so a visually suitable rod does not collide with an adjacent return wall.

Side extension and stack-back

Side extension helps cover the window edges and creates some space for open panels. Thick or full curtains may stack wider than a simple planning allowance, so the actual fabric and heading matter.

What this guide does not determine

Rod diameter, brackets, anchors, substrate, span limits, curtain weight, and load capacity are product- and installation-specific. Use the hardware instructions or a qualified installer for those decisions.

Before you order or cut

Measure the actual window and selected product. Finished sizes, fullness, header take-up, hardware geometry, and manufacturer tolerances vary. Fabric can shrink, stretch, or behave differently by composition. Measurements do not guarantee fit, privacy, water containment, installation, load capacity, or structural safety. Use the selected product instructions, and have a professional workroom verify expensive custom-fabric orders.

SOURCE NOTES

What this page is based on

Measurements here combine mathematical results with labeled commercial conventions and design recommendations. Disagreements are kept as ranges rather than averaged into a false standard.

  1. BETYDLIG/RÄCKA/HUGAD buying guide — Measure your windowIKEA · reviewed 2026-09-11

    Primary manufacturer guide: add at least 6 in each side, add 6 in above, and use 2–2.5× rod width for panel planning.

  2. VIDGA — How to measure your windowsIKEA · reviewed 2026-09-11

    Current manufacturer track-system guide with measured-window diagrams, minimum side extension, stack-back planning, and hanging-point length references.

  3. Buying curtainsJohn Lewis & Partners · reviewed 2026-09-11

    Retailer/workroom guidance on pole extension, hanging references, sill/floor endpoints, ready-made metric ranges, and double fullness.