# Feet & Inches Calculator — Add, Subtract & Convert to Metric > Free feet-and-inches calculator: add, subtract, multiply and divide feet-inch-fraction measurements on a running tape, then convert the total to decimal feet, inches, yards, mm, cm and metres — with a fraction reference and tick ruler, all in your browser. Add, subtract, multiply and divide feet-inch-fraction measurements — and convert the running total to metric instantly. - **HTML page:** https://siteometry.com/en/tools/feet-inches-calculator - **Category:** [Framing & Carpentry](https://siteometry.com/en/tools/category/framing-carpentry) - **Figures live on the page:** tables, diagrams and worked figures the text refers to ("the table below") are drawn by the page and are not reproduced here. Each section below links to its anchor on the page. - **Runs in the browser:** Siteometry calculators need no account and send no input anywhere — every number below is computed on the visitor's own device. ## How to add and convert feet and inches in 4 steps 1. **Enter your first measurement** — Type your starting length into the first row — for example 5 ft 3 1/2 in, 5' 3-1/2", 63.5 in or 1610 mm. The calculator reads feet, inches, fractions, decimals and metric input. 2. **Add more rows** — Press Add row for each further measurement and choose its operator: add, subtract, multiply or divide. Multiply and divide take a plain number, such as ×3 or ÷5. 3. **Choose the precision** — Pick 1/8, 1/16 or 1/32 of an inch. Every feet-and-inches reading and the ruler round to that fraction; the underlying value stays exact. 4. **Read and convert the total** — The running total updates live in feet and inches. The conversion table shows it in decimal feet, decimal inches, yards, millimetres, centimetres and metres — copy any row or a shareable link. _On the page: https://siteometry.com/en/tools/feet-inches-calculator#howto_ ## Feet and inches calculator with instant metric Carpentry, framing and DIY measurements are written in feet, inches and fractions — 5 ft 3 1/2 in, 8' 0-11/16", a stack of cuts that has to add up to the length of a wall. Adding those by hand is error-prone: you carry sixteenths, borrow inches, and one slip throws the whole run off. This calculator does it for you on a running tape, then shows the total in every unit you might need. Type each measurement on its own row and pick an operator — add, subtract, multiply or divide. The tape folds top to bottom into a live running total, shown in feet, inches and your chosen fraction. That same total is converted at once to decimal feet, decimal inches, yards, millimetres, centimetres and metres, and drawn on a tick ruler so you can see exactly where the fractional inch lands. Everything runs in your browser: nothing you type is uploaded, and there is no account to create. Pick the precision — 1/8, 1/16 or 1/32 of an inch — and every feet-and-inches reading and the ruler round to it. _On the page: https://siteometry.com/en/tools/feet-inches-calculator#feet-inches-intro_ ## How to use the feet and inches calculator The calculator works like an adding-machine tape. The first row is your starting measurement; every row after it applies its operator to the running total, from top to bottom, with no operator precedence. Multiply and divide take a plain number — for example ×3 to repeat a cut three times, or ÷5 to split a length into five equal pieces. _On the page: https://siteometry.com/en/tools/feet-inches-calculator#how-it-works_ ## Inch fraction reference The table below lists each sixteenth of an inch alongside its decimal-inch and millimetre equivalent — the conversion carpenters reach for most often. Every value is computed the same way the calculator rounds, so what you read here matches the tool. _On the page: https://siteometry.com/en/tools/feet-inches-calculator#fraction-reference_ ## Reading the ruler The ruler always shows a single inch, graduated to your chosen precision. The tallest ticks mark the halves and quarters, the shortest the finest fraction — the standard tape convention. The examples below show where common fractions fall. _On the page: https://siteometry.com/en/tools/feet-inches-calculator#ruler-samples_ ## Frequently asked questions ### How do I add feet and inches together? Enter each measurement on its own row — for example 5 ft 3 1/2 in on the first row and 8 ft 0 11/16 in on the next with the + operator. The calculator carries the fractions and inches for you and shows the running total in feet, inches and your chosen fraction. You can keep adding rows for a whole cut list. ### Can I subtract one measurement from another? Yes. Choose the − (subtract) operator on any row and the calculator takes that measurement off the running total — useful for working out an offcut or the gap left after a run of boards. ### How do multiply and divide work? Multiply and divide use a plain number, not another measurement. Use ×3 to repeat a cut three times, or ÷5 to split a length into five equal pieces. The result stays a length, so the conversion table and ruler still apply. ### How do I convert feet and inches to metric? The conversion table under the tape always shows the running total in millimetres, centimetres and metres alongside decimal feet, decimal inches and yards. You can also enter metric measurements (mm, cm or m) directly on any row and mix them with imperial input. ### What precision should I use? Framing and rough carpentry usually work to 1/16 of an inch, which is the default. Choose 1/8 for quick estimates or 1/32 for fine joinery. The precision only changes how the feet-and-inches readings and ruler are rounded — the underlying calculation is always exact. ### How should I type a measurement? Use feet marks (' or ft) and inch marks (" or in), with fractions as n/d. All of these work: 5 ft 3 1/2 in, 5' 3-1/2", 5' 3.5", 63.5, 63.5 in, 5.29 ft, 3/16, and metric such as 1610 mm or 1.61 m. A bare number is read as inches. A hyphen without a unit, like 5-3, is rejected because it is ambiguous — add a unit. ### Is the calculator private? Yes. Every calculation runs entirely in your browser. Nothing you enter is sent to any server, and only your last-used precision is remembered, in your own browser's local storage. _On the page: https://siteometry.com/en/tools/feet-inches-calculator#faq_ ## Related construction calculators Once you have a length in feet and inches, carry it into the calculator that turns it into boards, studs, framing, concrete or area — these siblings pick up where the tape leaves off. - [Rafter Length Calculator](https://siteometry.com/en/tools/rafter-length-calculator) - [Slope & Grade Calculator — Percent, Degrees, Ratio & Fall](https://siteometry.com/en/tools/slope-grade-calculator) - [Deck & Patio Cost Calculator](https://siteometry.com/en/tools/deck) - [Deck Railing & Baluster Spacing Calculator](https://siteometry.com/en/tools/deck-railing-calculator)