What scale are house plans?

¼ in = 1 ft (1:48) for floor plans; ⅛ in = 1 ft for larger buildings.

How do I check a print's scale?

Measure a known dimension and divide real by printed length.

What does ¼ in = 1 ft mean?

Each quarter inch on paper equals one foot (1:48).

What scale for construction details?

1½ in or 3 in = 1 ft (1:8 or 1:4).

How do I print a PDF to scale?

Print at 100% (actual size), not fit to page.

Architectural scale converter

Pick the scale, measure on the drawing and get the real length; enter a real length to see how long it draws.

Real-world length

2.5 m

Real-world length2.5 m
Drawing length for the real length entered8 cm
Scale factor50

Use my prices

Your prices per language/currency. Used when you enable “Use my prices” in calculators. My prices →

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How it's calculated (visible formula)

real = drawing × scale factor; drawing = real ÷ scale factor

Net geometric measurement, no waste.
Adjustable waste % for cuts and breakage.
Purchase rounded up to sellable units (boxes, bags, buckets, boards).

See methodology and formula versions

How to calculate it, step by step

Check the scale in the title block.
Select it in the calculator.
Measure the drawing length.
Get the real length.
To draw, enter the real length and get the drawing length.

Worked example: ¼ in = 1 ft (1:48), 2 in measured

2 in × 48 = 96 in = 8 ft
A 13 ft wall draws at 13 × 12 ÷ 48 = 3.25 in

→ 2 in is 8 ft; 13 ft draws as 3¼ in.

Common mistakes

Measuring a print scaled to a different sheet size.
Confusing 1:50 and 1:500.
Trusting the graphic scale on a resized PDF.

Pro tips

Verify scale with a known dimension — PDFs often print scaled.
Use a multi-scale architect's ruler on site.
Note the scale on any printed excerpt.
Don't measure old permit drawings without checking.

From calculation to quote

Add labour, overhead and your margin, and generate the professional PDF.

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FAQs

What scale are house plans?: ¼ in = 1 ft (1:48) for floor plans; ⅛ in = 1 ft for larger buildings.
What is 1:96?: ⅛ in per foot.
How do I check a print's scale?: Measure a known dimension and divide real by printed length.
What does ¼ in = 1 ft mean?: Each quarter inch on paper equals one foot (1:48).
What scale for construction details?: 1½ in or 3 in = 1 ft (1:8 or 1:4).
How do I print a PDF to scale?: Print at 100% (actual size), not fit to page.

Sources and standards

Maintained by Srikanta M · Formula v1.0.0 · Verified 2026-09-10 · Updated 2026-09-10 · Limits: quantity estimation, not structural design or site supervision.