ReceiptKitReceiptKit / Free tools / Feet and inches calculator
Feet and Inches Calculator
Type two lengths the way you write them, such as 5' 3 1/2" and 2' 7 3/4", pick add, subtract, multiply, divide or how many fit, and read the answer in feet and inches, decimals and millimeters. You can also add up a list. 5' 3 1/2" plus 2' 7 3/4" is 7' 11 1/4".
Updated · Sources re-checked by
7' 11 1/4"
| Decimal feet | 7.9375 ft |
| Decimal inches | 95.25 in |
| Millimeters | 2,419.35 mm |
| Centimeters | 24.19 cm |
| Meters | 2.4194 m |
You can type 5' 3 1/2", 5 ft 3 1/2 in, 5'3-1/2", 63.5 (inches), 3 m or 30 cm. A minus sign on an answer means the second length is longer. Nothing you type is saved or sent anywhere.
How feet and inches are calculated
Every length is turned into inches first: feet × 12 plus inches plus the fraction. Add and subtract work on the inches. To multiply or divide, the length is multiplied or divided by a plain number. How many fit divides one length by another, rounds down to whole pieces and shows what is left. The answer is rounded to the nearest fraction you choose, from 1/2 down to 1/64 of an inch, and shown as feet and inches, as decimal feet and inches, and in millimeters, centimeters and meters (1 inch = 25.4 mm exactly).
| Fraction | Decimal inches | Millimeters |
|---|---|---|
| 1/16 | 0.0625 | 1.59 |
| 1/8 | 0.125 | 3.18 |
| 3/16 | 0.1875 | 4.76 |
| 1/4 | 0.25 | 6.35 |
| 3/8 | 0.375 | 9.52 |
| 1/2 | 0.5 | 12.7 |
| 5/8 | 0.625 | 15.88 |
| 3/4 | 0.75 | 19.05 |
| 7/8 | 0.875 | 22.22 |
| 15/16 | 0.9375 | 23.81 |
| Inches | Feet and inches | Decimal feet |
|---|---|---|
| 6" | 6" | 0.5 |
| 18" | 1' 6" | 1.5 |
| 30" | 2' 6" | 2.5 |
| 42" | 3' 6" | 3.5 |
| 66" | 5' 6" | 5.5 |
| 90" | 7' 6" | 7.5 |
| 144" | 12' 0" | 12 |
Worked examples: five common jobs
- Add: 5' 3 1/2" is 63.5 in and 2' 7 3/4" is 31.75 in. Together 95.25 in = 7' 11 1/4", which is 7.9375 ft or 2,419.35 mm.
- Subtract: 10' is 120 in and 3' 4 5/8" is 40.625 in. The difference is 79.375 in = 6' 7 3/8".
- Multiply: 8' 3" is 99 in, times 3 is 297 in = 24' 9".
- Divide: 10' 3" is 123 in, divided by 5 is 24.6 in, which rounds to 2' 0 5/8" at 1/16 in.
- Fit: 12' 6" is 150 in, divided by 16 in is 9 whole pieces with 6" left. A list of 2 × 8' 3", 3 × 5' 6 1/2" and 1 × 2' 9" adds up to 35' 10 1/2".
Common questions
How do I add feet and inches?
Change each length to inches, add them, then change the total back: 12 inches make a foot. For 5' 3 1/2" plus 2' 7 3/4", the inches add to 95.25, which is 7' 11 1/4". The calculator does this and keeps the fractions.
How do I type a length?
Any common way works: 5' 3 1/2", 5 ft 3 1/2 in, 5'3-1/2", or just 63.5 for inches. You can also type 3 m or 30 cm and it converts.
How do I subtract feet and inches?
Subtract the inches, then convert the result back. If the answer is negative the calculator shows a minus sign, which means the second length is the longer one.
How do I divide a length into equal parts?
Choose divide and type the number of parts. 10' 3" divided by 5 gives 2' 0 5/8" for each part at 1/16 in. Set a finer fraction if you need more precision.
How many pieces fit in a length?
Choose how many fit, type the length and the piece size. 12' 6" holds nine 16" pieces with 6" left over, which is handy for studs, pickets and tiles.
What fraction should I round to?
Most tape measures show 1/16 of an inch, so 1/16 is a good default. Rough framing is often fine at 1/8, and fine woodwork may want 1/32 or 1/64.
More invoice tools
- Invoice Generator: Free invoice maker: items, tax, discount, deposit and balance due, with a clean PDF and no watermark.
- Contractor Invoice Template: Contractor invoice with job site, license number, labor, materials, deposit and balance due, as a clean PDF.
- Construction Invoice Template: Construction invoice for progress billing with project details, retainage held back and payments received.
- Freelance Invoice Template: Freelance invoice by the hour or a fixed fee, with expenses, an advance already paid and your currency.
- Blank Invoice Template: A blank invoice to print and fill in by hand, or fill online and let the totals work themselves out.
- Simple Invoice Template: A plain invoice in about a minute: your name, the client, items and one tax rate, as a clean PDF.
- Service Invoice Template: Service invoice with the service date and place, parts and fees, tax and payments, as a clean PDF.
- Trucking Invoice Template: Trucking invoice with a load sheet: route, miles, rate per mile, fuel surcharge and detention, as a PDF.
- Towing Invoice Template: Towing invoice built call by call: vehicle, call-out, extra miles, after-hours surcharge and storage days.
- Moving Company Invoice Template: Moving invoice that starts with a crew calculator: movers, hours, minimum hours, truck fee, boxes and stairs.
- Auto Repair Invoice Template: Auto repair invoice with a vehicle card, a parts table with part numbers, a labor table in hours and shop supplies.
- Roofing Invoice Template: Roofing invoice that measures first: footprint and pitch give squares, then install, tear-off and flashing are priced.
- Painter Invoice Template: Painting invoice built room by room: walls, ceilings, coats, gallons of paint and a price per square foot.
- Cleaning Service Invoice Template: Cleaning invoice priced by home size and add-on tasks, with a schedule that sets the repeat-visit discount.
- Free Estimate Template: Free estimate template with items, a contingency, a likely range around the total, a validity period and an acceptance signature.
- Quote Template Generator: Quote generator with a fixed price, tax, a payment schedule that adds up exactly, a validity period and an acceptance signature.
- Work Order Template: Work order template with priority, site, assignee, a task checklist, labor and materials, and a customer sign-off.
- Receipt Template Generator: Receipt generator with the payment method, date paid, amount received and balance remaining, as a clean PDF.
- Change Order Template: Change order with added work, credits for removed work, the revised contract total, the schedule change and a client signature line.
- Deposit Invoice Template: Deposit invoice that starts from the contract total: a percent or a fixed deposit, what was received and what is still due.
- Progress Invoice Template: Progress invoice built from a schedule of values: percent done before and this period, and what is billed now.
- Landscaping and Lawn Care Invoice Template: Landscaping and lawn care invoice from a service menu priced per visit, with a period total and a season total.
- Free Invoice Template: Free invoice template: set your details and download Word or Excel, opens in Google Docs and Sheets too.
- Invoice Template for Word: Free Word invoice template (.docx): choose rows, tax and extras, then edit every word in Word.
- Invoice Template for Excel: Free Excel invoice template (.xlsx) with formulas for amounts, tax, total and balance due.
- Invoice Template for Google Docs: Use the free invoice template in Google Docs or Google Sheets: download, upload to Drive, open and edit.
- Timesheet Template: Free weekly or two-week timesheet (Excel with formulas, printable Word) with overtime and pay.
More calculators
- Concrete Calculator: Cubic yards, cubic meters and 40, 50, 60 and 80 lb bags for slabs and round columns, with waste.
- Concrete Slab Calculator: Concrete, bags and gravel base for one slab, with thickness presets and common size tables.
- Concrete Bag Calculator: How many 40, 50, 60 or 80 lb bags for a slab or fence posts, with total weight.
- Cubic Yard Calculator: Cubic yards for soil, mulch, gravel and more: several shapes, conversions, loads and bags.
- Gravel Calculator: Cubic yards and tons of gravel for driveways, paths and bases, with layers, loads and cost.
- Stair Calculator: Number of steps, exact riser, tread run, angle and slope length from the total rise, with a code check.
- Stair Stringer Calculator: Stair stringer layout: framing square numbers, bottom cut, throat depth, board length and stringer count.
- Roof Pitch Calculator: Convert rise over 12, degrees and percent slope, and get slope factor, rafter length and ridge height.
- Board Foot Calculator: Board feet for several boards at once, with quarter notation, cost, cubic feet and cubic meters.
- Paver Calculator: Number of pavers, pallets, gravel base, bedding sand and edge restraint for a patio, path or driveway.
- Square Footage Calculator: Add rooms and shapes in feet, inches or meters, subtract cutouts, and see sq ft, sq yd, m² and acres.
- Paint Calculator: Gallons of paint room by room: walls, doors, windows, ceiling and coats, with the amount to buy.
- Paint Calculator by Square Feet: Gallons of paint from a square footage: coats, coverage, waste, quarts to buy and cost per square foot.
- Mulch Calculator: Cubic yards for delivery and bags from the store for several beds, with a cost for each way.
- Drywall Calculator: Sheets of drywall, boxes of joint compound and screws for rooms with doors, windows and ceilings.
- Markup Calculator: Markup vs margin: enter a cost and a markup, a margin or a price, and see the other two and the profit.
- Profit Margin Calculator: Gross and net profit and margin for a job or a month, and the price that reaches a target margin.
- Contractor Hourly Rate Calculator: The hourly rate to charge from your wanted pay, tax estimate, overhead, profit cushion and billable hours.
- Labor Cost Calculator: True labor cost for a crew: wages, overtime and burden, the cost per hour and a bill-out price.
- Fence Calculator: Posts, panels or pickets and rails, post length and bags of concrete for runs of fence with gates.
- Roofing Calculator: Roof sections with pitch to squares, shingle bundles with waste, underlayment rolls, drip edge and cost.
- Roof Square Calculator: Square feet to roofing squares from an area, a flat plane or a footprint with pitch, with bundles and a price.
- Wallpaper Calculator: Wallpaper rolls by the drop method: strips per wall, pattern repeat, strips per roll and rolls to order.
- Insulation Calculator: Depth for a target R-value from the R per inch on your label, with volume, existing layer and packages.
- Plywood Calculator: Sheets of plywood for floors, walls and roofs from areas with openings taken away, by sheet size, with cost.
- Team Payroll Calculator: Employer cost of a team of 10 to 50 workers: hourly and salaried, overtime, burden, cost per period and per year.
- Overtime Calculator: Overtime pay at 1.5x or your own multiplier, double time, and the effective hourly rate.
- Hourly to Salary Calculator: Hourly rate to yearly, monthly, weekly and daily pay, and salary back to hourly, with unpaid weeks.
Sources
- Foot (unit): 1 foot = 12 inches = 0.3048 meters exactly (checked October 28, 2026)
- Inch: 1 inch = 25.4 millimeters exactly, and the fractions used on a tape measure (checked October 28, 2026)
- International yard and pound agreement (1959): the exact definitions of the inch and the foot (checked October 28, 2026)
This calculator is an aid for planning. Always check measurements on the job, and remember that real boards and tape measures have small errors. Round to the fraction your work needs.