Board Foot Calculator

Last updated: June 2026

Thickness

Board width

Board length

Quantity

boards

Waste

Board feet

25.17 bd ft

Metric volume

0.059 m3

Formula

board feet = thickness(in) x width(in) x length(ft) x quantity / 12 x waste allowance. Metric volume = thickness x width x length x quantity x waste allowance.

About this calculator

The Board Foot Calculator estimates timber volume using the board-foot measure common in hardwood, imported timber, and woodworking supply. It is useful when comparing timber sold by volume with metric dimensions used on a UK cutting list.

Board Foot Calculator method

The calculator uses metric project dimensions, applies the material formula shown below, and then adds any waste or allowance entered. Quantities are rounded up where materials are normally purchased as whole boards, sheets, blocks, rolls, bags, or packs.

board feet = thickness inches x width inches x length feet x quantity / 12 x waste allowance
metric volume m3 = length m x width m x thickness m x quantity
order volume = calculated volume x (1 + waste percentage)

How to use the Board Foot Calculator

Enter the board thickness, width, length, and quantity.
Use the unit system shown by the supplier or convert carefully first.
Add waste for knots, defects, planing, and cutting losses.
Compare the board-foot result with the supplier price per board foot.
Use the metric volume result when checking cubic metre pricing.

Worked examples

Hardwood shelf boards

Input: 25mm thick, 200mm wide, 2.4m long, 4 boards

Calculation: The calculator converts dimensions to the board-foot method and multiplies by quantity.

Result: The result gives a volume estimate to compare with supplier pricing.

Small furniture project

Input: Several boards plus 15% waste for cutting and defects

Calculation: Base timber volume is increased by the waste allowance.

Result: The order estimate helps avoid running short during matching and machining.

When this calculator is useful

Use it before ordering materials, comparing supplier pack sizes, or checking whether a first estimate is realistic. Keep the result with your measured dimensions so you can update the calculation if the project size changes.

Inputs that affect the result

Nominal vs actual size: Timber may be sold by nominal size but supplied smaller after planing.
Defects: Knots, splits, sapwood, and movement can reduce usable yield.
Moisture and machining: Planing and thicknessing can remove material beyond the visible cut size.

Common mistakes to avoid

Check 1: Do not mix inches, feet, millimetres, and metres without converting deliberately.
Check 2: Live-edge or waney-edge boards may have variable usable width.
Check 3: Board-foot pricing does not include delivery, machining, or grading differences.

Material planning notes

Planning point	Why it matters
Measure finished area	Use the actual finished dimensions after allowing for openings, edges, posts, slopes, or returns.
Allow for waste	Cuts, breakages, joins, pattern matching, awkward shapes, and site handling usually mean ordering more than the exact calculated amount.
Round purchase quantities up	Most materials are bought as full boards, sheets, bags, blocks, rolls, packs, or bulk deliveries.
Check supplier specifications	Coverage, density, sheet size, block size, and pack size vary by product and supplier.

Limitations and safety

This calculator is for general project planning only. It does not replace a structural design, building regulations advice, manufacturer instructions, supplier specifications, or a competent tradesperson. Projects involving structure, roofs, retaining walls, foundations, drainage, electrics, gas, or safety-critical work should be checked properly before buying materials or starting work.

Frequently asked questions

Should I order exactly the calculated quantity?

Usually no. Order in the nearest practical pack, board, sheet, bag, roll, or delivery quantity, and keep a sensible waste allowance for cuts and mistakes.

What waste allowance should I use?

Simple rectangular jobs may only need 5-10%. Patterned, angled, fragile, or irregular projects may need more. The right allowance depends on the material and layout.

Why might my supplier quantity differ?

Suppliers use specific product sizes, densities, coverage rates, and pack quantities. Use the calculator as a planning estimate, then compare it with the product label or datasheet.

Can I use this for professional building work?

It can help with a rough take-off, but professional work should be checked against drawings, specifications, site conditions, and relevant UK rules or standards.

What measurements should I double-check?

Check length, width, depth, height, spacing, openings, pitch, and units. A small unit mistake can change a material order by a large amount.

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What does this mean?

This calculator is designed to help you understand the likely number before you make a decision or start an application.

Your result should be checked against official UK guidance, especially if your circumstances include dependants, exemptions, prior leave, or a complex immigration history.

Treat the figure as a planning tool rather than legal advice. Where the answer affects an application deadline or major payment, speak to an authorised adviser.