Reference sheet / internal leaf dimensions

UK door sizes: metric and imperial chart

Common UK internal door leaves are sold in imperial-derived and metric families. Read every size below as width × height × thickness, then measure the actual leaf or opening: a listed leaf size is not a frame-opening size or a promise that the door will fit.

13 sourced leaf sizes

Direct answer

Width comes first.

On this page, 762 × 1981 × 35 mm means a leaf 762 mm wide, 1981 mm high and 35 mm thick. That order matters: reversing width and height can turn a recognisable door size into a meaningless record. Keep the three values together and keep the unit beside them.

The two families are not interchangeable labels for one catalogue. The imperial family uses familiar foot-and-inch names with conventional millimetre listings, mostly at 1981 mm high in the verified data. The metric family in the same evidence uses 2040 mm height and 40 mm thickness. These are reference dimensions for common internal leaves, not an inventory of every door made in the UK.

Family A / imperial-derived

Imperial internal door sizes

The foot-and-inch name is shown exactly as recorded in the evidence; the ordering column repeats the millimetre leaf dimensions as width × height × thickness.

Verified imperial-family internal door leaf dimensions
Imperial family labelWidth (mm)Height (mm)Thickness (mm)W × H × T (mm)
1 ft 3 in × 6 ft 6 in381198135381 × 1981 × 35
1 ft 6 in × 6 ft 6 in457198135457 × 1981 × 35
1 ft 9 in × 6 ft 6 in533198135533 × 1981 × 35
2 ft 0 in × 6 ft 6 in610198135610 × 1981 × 35
2 ft 3 in × 6 ft 6 in686198135686 × 1981 × 35
2 ft 6 in × 6 ft 6 in762198135762 × 1981 × 35
2 ft 9 in × 6 ft 6 in838198135838 × 1981 × 35
2 ft 8 in × 6 ft 8 in813203235813 × 2032 × 35

Family B / metric

Metric internal door sizes

These rows share a 2040 mm height and 40 mm thickness in the accepted dataset. “Metric” identifies the family; it does not mean that an opening can be rounded to the nearest row.

Verified metric-family internal door leaf dimensions
FamilyWidth (mm)Height (mm)Thickness (mm)W × H × T (mm)
Metric526204040526 × 2040 × 40
Metric626204040626 × 2040 × 40
Metric726204040726 × 2040 × 40
Metric826204040826 × 2040 × 40
Metric926204040926 × 2040 × 40

Both complete tables are present in the HTML. The optional filter below only hides rows on screen; it does not replace or generate dimensions.

Optional finder / no recommendation

Filter by a dimension you already have

Choose a family, then enter a width, height or both. In inch mode the filter multiplies the entry by 25.4 and rounds that conversion to the nearest whole millimetre before comparing it with the recorded rows. This is a lookup aid only. A zero-result search means no row in this limited reference set matched; it does not mean a suitable product is unavailable.

Conversion reference: inches × 25.4 = millimetres; millimetres ÷ 25.4 = inches. For example, 30 in converts to 762 mm. The conventional 6 ft 6 in name equals 78 in, or 1981.2 mm by arithmetic, while the accepted imperial-family row is recorded as 1981 mm. Preserve the listed row rather than silently rewriting it.

Filter the two visible tables

All 13 reference rows are visible. Enable JavaScript only if you want to filter them.

Leaf ≠ lining ≠ opening

External doors and frames need a declared measuring mode.

An external or front door may be supplied and specified as part of a doorset rather than as a loose internal leaf. The leaf, the inside of an existing frame or lining, and the wall or structural opening are different measuring surfaces. Do not take a width from one mode and a height from another, and do not add an assumed frame margin to a table row.

The verified merchant evidence expressly says there is no single standard UK door-frame size. That is why this page does not publish a universal “opening for an 838 mm door” row. Frame sections, linings, rebates, thresholds, seals, installation clearances and product instructions can change what must be recorded. See the Door Superstore terminology and frame-size source note for the limited claim, then use the dimensions supplied for the exact product or system.

If the words around the opening are unclear, compare door frame, lining and casing terms before writing numbers down. Terminology varies, so label the physical points measured as well as the part name.

Third dimension

Thickness changes the record.

Width and height attract attention because they describe the face of the leaf, but thickness affects how that leaf relates to the rebate or loose stop, the selected hinges and other product-specific parts. The accepted tables show 35 mm for the imperial family and 40 mm for the metric family. Those values describe these rows only; they are not a rule for external doors, fire doors or every internal construction.

Record thickness directly from the existing leaf only when that is the declared mode. If you are measuring an empty frame opening, write down the rebate or stop condition separately rather than calling its depth “door thickness”. If you are measuring a wall opening, the result is further removed from a finished leaf size.

The Everest measuring source distinguishes an existing door, the inside of a frame and a brick-to-brick opening. Our recorder keeps the first two common modes explicit and reports ranges without selecting a size.

Next sheet

Record the opening before comparing products.

Use the three-point door measurement recorder to keep three widths, three heights and the declared mode on one printable sheet, then plan how to hang the door from that measured record. It reports the minimum, maximum and spread; it still does not promise a fit or choose an item to order.

Measure first