Sf To Lf Calculator
Square feet measure an area, linear feet measure a length, and the width of your material is the bridge between them. This calculator converts both ways: enter square footage and board width to get linear feet of flooring, trim or fabric, or enter linear feet and width to get the area that length will cover.
Result
Quick Answer
Divide square feet by the material width in feet to get linear feet: 500 sq ft of 6-inch (0.5 ft) boards needs 1,000.00 linear feet. Going the other way, multiply linear feet by width: 50 linear feet of 0.5 ft boards covers 25.00 square feet. There is no fixed conversion without the width, which is why the tool asks for it. The calculator above is pre-filled with the 500 sq ft example.
Key takeaways
- Linear feet = square feet divided by width in feet. Square feet = linear feet times width in feet. Width is the whole conversion; without it the question has no answer.
- Enter the width in FEET. A 6-inch board is 0.5 feet (6 divided by 12). Forgetting the inches-to-feet step is the most common mistake and produces an answer 12 times too small or too large.
- Use the actual face width that covers the surface, not the nominal size. A 1x6 board is really 5.5 inches wide, and tongue-and-groove flooring loses the tongue to the joint.
- The headline result now includes your waste allowance, and the net figure stays visible in the calculation line. The pre-filled 10% suits straight runs; use 15% for diagonals and patterns. Flooring suppliers treat 10% as the standard allowance.
- Fencing and baseboard trim are measured by perimeter, not converted from an area. This tool converts area to material length; it does not lay out a fence run.
- Quick Answer
- How to use the SF to LF calculator
- The formula: square feet to linear feet
- Worked example: 500 square feet of 6-inch boards
- Linear feet needed per 100 square feet, by board width
- Mistakes this conversion punishes
- Where the conversion is used
- What competing calculators miss
- Frequently asked questions
- Add This Calculator to Your Website
- References
How to use the SF to LF calculator
Choose the direction, enter the area, the width, and the waste allowance, and click Calculate. Results stay hidden until you do.
- Square feet to linear feet: enter the area (500 pre-filled) and the board width in feet (0.5 pre-filled for 6-inch boards). The net answer is 1,000.00 LF, and with the pre-filled 10% waste allowance the amount to order is 1,100.00 LF.
- Linear feet to square feet: switch the direction. The pre-filled 50 LF at 0.5 ft width covers 25.00 SF, useful when a supplier quotes coverage per length.
- Convert inches to feet first: divide the board width in inches by 12. Six inches is 0.5 ft, 3.25 inches is about 0.27 ft, a 12-foot carpet roll is 12 ft.
- Read the three result lines: the headline answer, the calculation it ran (for example 500.00 sq ft divided by 0.50 ft), and the width it used.
- Waste allowance: the tool applies the waste allowance you enter (10% pre-filled for straight installs, 15% for diagonal or patterned work) to the net figure, and the net figure stays visible in the calculation line, so the waste math stays checkable.
If you price material by the foot as well as by length, the cost per linear foot calculator turns a per-foot price into a project total, the deck material calculator sizes a whole deck project including boards, and the fence price calculator estimates fence runs priced by the linear foot.
The formula: square feet to linear feet
The whole conversion is one division, and the reverse is one multiplication:
Square feet = Linear feet × Width in feet
Width in feet = Width in inches ÷ 12
With waste = Net linear feet × (1 + waste percent ÷ 100). The pre-filled 10% gives 1,000.00 × 1.10 = 1,100.00 LF to order; change it to 15% for diagonal or patterned work
Why division? A board of width w feet covers w square feet for every foot of its length, so the length needed is the total area divided by the area each foot of board covers. For people who think in inches: linear feet = (square feet × 12) ÷ board width in inches, which is the same division with the 12 folded in. Use the actual exposed face width: for tongue-and-groove flooring that is the face, not the full board including the tongue, and for deck boards add the gap between boards to the width, a point several flooring guides stress because nominal sizes mislead.
Worked example: 500 square feet of 6-inch boards
The pre-filled run divides 500 square feet by the 0.5-foot board width to get 1,000.00 linear feet. Here it is beside the reverse run and the most-asked width variation, every cell produced by the tool.
| Run | Inputs | Result |
|---|---|---|
| Worked example: square feet to linear feet | 500.00 sq ft ÷ 0.50 ft | 1,000.00 LF |
| Reverse: linear feet to square feet | 50.00 ft × 0.50 ft | 25.00 SF |
| Same area, 3.25-inch planks (0.2708 ft) | 500.00 sq ft ÷ 0.27 ft | 1,846.15 LF |
| With 10% waste (worked example) | 1,000.00 × 1.10 | 1,100.00 LF to order |
The third row shows why width dominates the answer: the same 500 square feet needs 1,846.15 linear feet of narrow 3.25-inch planks but only 1,000.00 of 6-inch boards. The waste row is now a live input, prefilled at 10%: 500 sq ft / 0.5 ft gives 1,000.00 LF net and 1,100.00 LF to order, and the calculation line keeps the net figure beside the order figure so the allowance stays a deliberate choice rather than a hidden fudge.
Linear feet needed per 100 square feet, by board width
The most useful lookup in this topic: how many linear feet cover 100 square feet at common board widths. Every cell is a tool-verified net figure, before waste.
| Material | Width | LF per 100 sq ft | With 10% waste |
|---|---|---|---|
| Strip flooring | 2.25 in (0.1875 ft) | 533.33 | 586.67 |
| Plank flooring | 3.25 in (0.2708 ft) | 369.23 | 406.15 |
| Plank flooring | 5 in (0.4167 ft) | 240.00 | 264.00 |
| 1x6 board (5.5 in actual) | 5.5 in (0.4583 ft) | 218.18 | 240.00 |
| 1x8 board (7.25 in actual) | 7.25 in (0.6042 ft) | 165.52 | 182.07 |
| Carpet roll (12 ft wide) | 12 ft | 8.33 | 9.17 |
Linear feet per 100 sq ft: narrower boards need much more length
Mistakes this conversion punishes
Five errors account for most bad orders, and the tool is designed around the first three:
- Entering inches as feet: 6 entered as the width gives 83.33 LF for 500 sq ft instead of 1,000. The tooltip on the width field says feet, not inches, and the worked example shows 0.5 for a 6-inch board.
- Using nominal instead of actual width: a 1x6 board is 5.5 inches of actual face, not 6. At 100 square feet that is 218.18 LF versus 200.00, a 9% shortfall hiding inside one assumption.
- Ordering the net figure: cuts, defects and bad ends eat material. The industry standard is 10% extra for straight runs and up to 15% for diagonals and patterns, per flooring manufacturer guidance. The tool shows the net figure plus a badge reminder so the waste call stays yours.
- Measuring a fence from an area: fencing is a perimeter measured in a straight line, not an area divided by a width. A fence encloses a boundary; this tool sizes material that covers a surface.
- Confusing square feet with linear feet at the supplier: flooring is often priced per square foot and sold by the carton or the linear foot. Convert before you compare quotes, or two prices in different units will mislead you.
Where the conversion is used
Any material sold by length but bought to cover an area needs this bridge:
- Flooring: hardwood, laminate and vinyl plank are priced and cartoned by the square foot but run as linear boards. A 192 sq ft room with 5-inch boards needs 460.80 LF net, 506.88 with 10% waste, so order 507 LF.
- Decking: deck boards at 5.5 inches actual face width turn a 160 sq ft deck into 349.09 LF net before waste.
- Carpet and sheet goods: rolls come 12 feet wide, so a 180 sq ft room needs 15.00 LF of roll, 16.50 with 10% waste.
- Trim, baseboards and moulding: these are pure perimeter lengths, measured wall by wall, which needs no area conversion at all. For straight length totals the linear foot calculator handles the adding up. Convert from square feet only when the material must cover a surface, like wainscoting panels.
- Fabric and wallpaper: bolts have a fixed width, so yardage from an area follows the same division.
What competing calculators miss
The math is universal, so the page that wins is the one that keeps you from misusing it:
- FreeFastCalculator: the strongest rival tool, with waste percentage, price per linear foot and board counts for standard 8, 12 and 16 ft lengths. Its strength is the full ordering workflow; its weakness is complexity for a reader who just needs the conversion. This page does the one conversion in both directions and leaves the waste math visible and manual.
- calculators.sg: three input styles (single length, multiple pieces, area to length) plus a waste margin. Solid, but thin on the inches-to-feet trap that causes most errors.
- AllInOneGenerators: the best explainer of the three, with the plain statement that converting without width is mathematically impossible and a worked carpet-roll example (180 sq ft at 12 ft wide is 15 LF). Its tool buries that clarity under a long page.
- ToolsRiver: the only rival to stress actual versus nominal lumber width and even the saw-blade kerf, but it is a guide with no working calculator.
- LinearFeetCalc: a 76-tool hub covering freight linear feet and board feet. Breadth is the draw; the SF-to-LF path competes with dozens of siblings for attention.
- OneSDR: a bare converter with an inches-or-feet width dropdown. Fast, but no guidance at all on waste, face width or the perimeter distinction.
- ConstructlyTools: a per-100-square-feet board-width table with the face-width warning, closest in spirit to this page's lookup table. It lacks the reverse direction and any waste treatment.
- The gap this page fills: both conversion directions in one card, the width-in-feet requirement stated where the mistake happens, a face-width versus nominal-width warning with the 1x6 example, an honest net figure with the 10%/15% waste rule spelled out instead of hidden, and a clear statement that fencing is a perimeter job, which the old version of this page got wrong.
Frequently asked questions
No. Square feet measure area and linear feet measure length, so the width is the required bridge between them. Any answer given without a width is a guess, not a conversion. Enter the material width in feet and the tool divides the area by it.
Divide the inches by 12. A 6-inch board is 0.5 feet, a 3.25-inch plank is about 0.27 feet, and a 12-foot carpet roll is simply 12 feet. Skipping this step is the most common error and throws the answer off by a factor of 12.
Yes. Enter the waste percentage (10% pre-filled, 15% for diagonal and patterned installs) and the headline result is the amount to order; the net figure stays in the calculation line. 1,000 linear feet becomes 1,100 to order at 10%.
The actual face width that covers the surface. A 1x6 board is really 5.5 inches wide, and tongue-and-groove flooring loses the tongue inside the joint. Using the nominal 6 inches instead of 5.5 understates the length you need by about 9%.
Narrow boards need far more length to cover the same area. One hundred square feet needs 533.33 linear feet of 2.25-inch strip flooring but only 240.00 of 5-inch planks. If the number looks wrong, check that you entered the width in feet, not inches.
Only for material that covers a surface, like wainscoting panels. Fencing and baseboard trim are perimeter measurements: you add up wall lengths in a straight line, which needs no area conversion at all.
Multiply linear feet by the width in feet. Switch the calculator to the Linear Feet to Square Feet direction: 50 linear feet of 0.5-foot boards covers 25.00 square feet. This is handy when a supplier quotes coverage per length of roll or board.
A linear foot is one dimension, length only, used for trim, boards, pipe and fencing. A square foot is two dimensions, length times width, used for floors, walls and land. A 10-foot board is always 10 linear feet, but its square footage changes with its width.
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References
- National Institute of Standards and Technology. Final Notice on Deprecation of the U.S. Survey Foot. October 5, 2020. Accessed October 23, 2026.
- Albany Woodworks. Wood Flooring Beginner Guide: Buying Your Floor. Accessed October 23, 2026.
- WoodCo. WoodCo's Complete Guide to Wood Flooring. Accessed October 23, 2026.
- Hunker. The Flooring Guideline Most Homeowners Don't Find Out About Until It's Too Late. September 8, 2026. Accessed October 23, 2026.
- Natural Wood Floor Company. Measuring Guide for Wood Flooring. Accessed October 23, 2026.