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Carpet Calculator

Live answer19.01 m² carpet17.28 m² measured + 10% allowance · 5.19 linear m at 3.66 m roll width
Live result19.01 m² carpet17.28 m² measured + 10% allowance · 5.19 linear m at 3.66 m roll width
Formula used

Measured area = room length × room width. Planning area = measured area × (1 + waste percent ÷ 100). Approximate roll length = planning area ÷ roll width. Optional material cost = planning area × price per square metre.

This is the method behind the answer, so the result can be checked rather than simply trusted.

Live math canvas

Your numbers, formula and explanation together

Carpet Calculator: 19.01 m² carpet. 17.28 m² measured + 10% allowance · 5.19 linear m at 3.66 m roll width

Formula applied

The exact method behind this answer

CalculationTime keeps the method visible so the number can be checked instead of blindly trusted.

Measured area = room length × room width. Planning area = measured area × (1 + waste percent ÷ 100). Approximate roll length = planning area ÷ roll width. Optional material cost = planning area × price per square metre.
  1. Apply the formulaMeasured area = room length × room width. Planning area = measured area × (1 + waste percent ÷ 100). Approximate roll length = planning area ÷ roll width. Optional material cost = planning area × price per square metre.19.01 m² carpet17.28 m² measured + 10% allowance · 5.19 linear m at 3.66 m roll width

Your live breakdown

Current inputs in the calculation

These values come from the controls above and update when the calculator changes.

Room length
4.8 m
Measure the longest practical length of the room in metres.
Room width
3.6 m
Measure the widest practical width of the room in metres.
Waste / trimming allowance
10 %
Common planning allowances are often 5–15%, but pattern matching and stairs can need more.
Carpet roll width
3.66 m
Typical roll widths include 3.66 m / 12 ft and 4 m, but use the supplier width.
Material price
0 per m² optional
Optional material-only price. Labour, underlay, joins, delivery and stair work are not included.

Resulting answer

19.01 m² carpet

17.28 m² measured + 10% allowance · 5.19 linear m at 3.66 m roll width

Answer
19.01 m² carpet
Live support
17.28 m² measured + 10% allowance · 5.19 linear m at 3.66 m roll width

Assumptions used

What this answer assumes

Measured area first; allowance, roll width and supplier rounding second.

  • The room is treated as a simple rectangle; alcoves, closets, stairs and irregular edges need separate measurement or added allowance.
  • Waste allowance is a planning input, not a guarantee. Pattern matching, pile direction, seams and installer layout can change the order quantity.
  • Roll length is approximate and should be rounded using the supplier’s ordering increments and carpet width.
  • The optional cost is material-only arithmetic. It excludes underlay, gripper, trims, delivery, labour, removal, stairs and tax unless you include them separately.

Master’s Tip

How to use the result well

Master’s Tip: print the measured area and the allowance separately before ordering. A supplier or installer may choose a different seam layout, especially for patterned carpet, stairs, bay windows or rooms wider than the roll.

Printable record

What belongs in the saved calculation

Save the inputs, result, formula, assumptions, page URL and date together so the calculation can be reviewed later.

Room length
4.8 m
Measure the longest practical length of the room in metres.
Room width
3.6 m
Measure the widest practical width of the room in metres.
Waste / trimming allowance
10 %
Common planning allowances are often 5–15%, but pattern matching and stairs can need more.
Carpet roll width
3.66 m
Typical roll widths include 3.66 m / 12 ft and 4 m, but use the supplier width.

Allowance check

Carpet order quantity changes with waste and roll width

The measured room area is 17.28 m². With the current 10% allowance, the planning area is 19.01 m² before supplier rounding.

AllowancePlanning areaApprox. roll length
5%18.14 m²4.96 linear m
10%19.01 m²5.19 linear m
15%19.87 m²5.43 linear m

Use the printed report as a measurement note, then confirm seam layout, pattern repeat and order rounding with the supplier or installer.

Visual grid

This result measures part of the space you live in

Length, area, volume and material estimates are grid problems too: measure the space, account for edges and allowances, then turn the pattern into a number you can use.

Micro-timehours, minutes, shiftsHuman scaledays, weeks, projectsMacro-timemonths, years, calendars
Measured output19.01 m² carpet

Space calculations turn a real surface, room, run or volume into cells, edges and allowances that can be quoted, ordered or checked.

CalculationTime

Carpet Calculation Report

Report date:

19.01 m² carpet17.28 m² measured + 10% allowance · 5.19 linear m at 3.66 m roll width

Inputs

Room length
4.8 m
Room width
3.6 m
Waste / trimming allowance
10 %
Carpet roll width
3.66 m
Material price
0 per m² optional

Method

Measured area = room length × room width. Planning area = measured area × (1 + waste percent ÷ 100). Approximate roll length = planning area ÷ roll width. Optional material cost = planning area × price per square metre.

  1. For a 4.8 m × 3.6 m room, measured area is 4.8 × 3.6 = 17.28 m². A 10% allowance gives 17.28 × 1.10 = 19.008 m², shown as 19.01 m². With a 3.66 m roll width, approximate roll length is 19.008 ÷ 3.66 = 5.19 m.

Assumptions

  • The room is treated as a simple rectangle; alcoves, closets, stairs and irregular edges need separate measurement or added allowance.
  • Waste allowance is a planning input, not a guarantee. Pattern matching, pile direction, seams and installer layout can change the order quantity.
  • Roll length is approximate and should be rounded using the supplier’s ordering increments and carpet width.
  • The optional cost is material-only arithmetic. It excludes underlay, gripper, trims, delivery, labour, removal, stairs and tax unless you include them separately.

Notes

Use this space on the printed report for client, supplier, classroom, job-location, measurement, quote or approval notes.

Source: https://www.calculationtime.com/calculators/carpet-calculator

This report shows the calculation inputs, formula, assumptions and result for review. It is not legal, payroll, tax, engineering, financial or academic advice unless a qualified professional confirms the applicable rules.