[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"tool-content:en:square-footage-calculator":3,"glossary:en":57,"published-tools-en":107},{"id":4,"documentId":5,"slug":6,"intro":7,"howTo":8,"longContent":9,"createdAt":10,"updatedAt":11,"publishedAt":12,"locale":13,"name":14,"faq":15,"examples":40,"category":41,"seo":51,"localizations":56,"metaTitle":53,"metaDescription":54},306,"sywryipoqnbqnw4xdib3dvx0","square-footage-calculator","\u003Cp>Square footage is length times width, a formula this \u003Cstrong>square footage calculator\u003C\u002Fstrong> applies to every room at once. Each row takes a length and a width in feet or in meters, so rooms of 20 × 15, 14 × 12 and 12 × 11 come to \u003Cstrong>600 sq ft\u003C\u002Fstrong> (\u003Cstrong>55.74 m²\u003C\u002Fstrong>), with the share of the total shown beside each room. Past \u003Cstrong>4,000 sq ft\u003C\u002Fstrong> the total also reads in acres. The order line adds a waste allowance of \u003Cstrong>10%\u003C\u002Fstrong> by default, which turns those 600 sq ft of floor into \u003Cstrong>660 sq ft\u003C\u002Fstrong> to buy.\u003C\u002Fp>","\u003Col>\u003Cli>Pick feet or meters in the \u003Cstrong>Measured in\u003C\u002Fstrong> field, then set the waste allowance. \u003Cstrong>10%\u003C\u002Fstrong> suits most straight-lay flooring jobs and the field accepts anything from 0 to 50%.\u003C\u002Fli>\u003Cli>Type the length and the width of the first room. Use a dot for decimals such as 12.5, since the comma is reserved for separating one room from the next.\u003C\u002Fli>\u003Cli>Press \u003Cstrong>Add a room\u003C\u002Fstrong> for each extra space and name the rows. The room-by-room table then labels every line and flags the largest room, the one that drives the order.\u003C\u002Fli>\u003Cli>Read the total in sq ft and m², the acres line that appears above 4,000 sq ft and the order figure with waste already included.\u003C\u002Fli>\u003C\u002Fol>","\u003Ch2 id=\"how-do-you-calculate-square-footage\">How do you calculate square footage?\u003C\u002Fh2>\n\u003Cp>Square footage comes from multiplying the length of a floor by its width, both measured in feet, which gives an area expressed in square feet. Take a room of 20 ft by 15 ft: multiplied together the two figures give \u003Cstrong>300 sq ft\u003C\u002Fstrong>. That single rectangle covers the whole calculation for a room of that shape.\u003C\u002Fp>\n\u003Cp>A house repeats the same operation room by room. The three rows loaded by default, 20 × 15, 14 × 12 and 12 × 11, work out at 300, 168 and 132 sq ft, which the calculator adds into \u003Cstrong>600 sq ft\u003C\u002Fstrong> and splits into shares of \u003Cstrong>50%, 28% and 22%\u003C\u002Fstrong>. That share column tells which room drives the order, the living room alone carrying half of it.\u003C\u002Fp>\n\u003Cp>Wall to wall at floor level is the line to measure, since baseboards and door casings narrow a room by an inch or two higher up. A tape reads in feet and inches while the fields above take decimal feet, so the inches are divided by 12 before being typed in. A room of 12 ft 6 in goes in as \u003Cstrong>12.5\u003C\u002Fstrong> and one of 12 ft 8 in as \u003Cstrong>12.67\u003C\u002Fstrong>. Appraisers working to \u003Cstrong>ANSI Z765\u003C\u002Fstrong> measure to the nearest inch or the nearest tenth of a foot, then report the area to the whole square foot.\u003C\u002Fp>\n\n\u003Ch2 id=\"square-footage-of-a-room-not-rectangular\">How to calculate square footage of a room that is not a rectangle\u003C\u002Fh2>\n\u003Cp>Any shape that is not a rectangle gets broken into rectangles whose areas are then added together. An L-shaped living room splits along the inside corner of the L, so a section of 14 × 10 and a second of 8 × 6 give 140 sq ft and 48 sq ft for a total of \u003Cstrong>188 sq ft\u003C\u002Fstrong>, one row per part.\u003C\u002Fp>\n\u003Cp>Closets, alcoves and the floor inside a bay window take the same treatment, one rectangle per row, named so the breakdown stays legible. A curved bay has no exact rectangular equivalent; the usual approximation boxes the curve inside the smallest rectangle that contains it, which overstates the area by a few square feet. On a flooring order that overstatement disappears into the waste allowance, though it has to come out again before the figure goes into a listing.\u003C\u002Fp>\n\n\u003Ch2 id=\"common-room-sizes\">Square footage of common room sizes\u003C\u002Fh2>\n\u003Cp>A 10 × 12 room comes to \u003Cstrong>120 sq ft\u003C\u002Fstrong> and needs \u003Cstrong>132 sq ft\u003C\u002Fstrong> of flooring on the shelf at the default allowance. The rows below run those same two steps on the sizes that keep recurring in listings and flooring quotes, using \u003Cstrong>1 sq ft = 0.0929 m²\u003C\u002Fstrong>.\u003C\u002Fp>\n\u003Ctable>\n\u003Cthead>\u003Ctr>\u003Cth>Room size (ft)\u003C\u002Fth>\u003Cth>Square footage\u003C\u002Fth>\u003Cth>In m²\u003C\u002Fth>\u003Cth>Order with 10% waste\u003C\u002Fth>\u003C\u002Ftr>\u003C\u002Fthead>\n\u003Ctbody>\n\u003Ctr>\u003Ctd>8 × 8\u003C\u002Ftd>\u003Ctd>64 sq ft\u003C\u002Ftd>\u003Ctd>5.95 m²\u003C\u002Ftd>\u003Ctd>70.4 sq ft\u003C\u002Ftd>\u003C\u002Ftr>\n\u003Ctr>\u003Ctd>10 × 12\u003C\u002Ftd>\u003Ctd>120 sq ft\u003C\u002Ftd>\u003Ctd>11.15 m²\u003C\u002Ftd>\u003Ctd>132 sq ft\u003C\u002Ftd>\u003C\u002Ftr>\n\u003Ctr>\u003Ctd>12 × 12\u003C\u002Ftd>\u003Ctd>144 sq ft\u003C\u002Ftd>\u003Ctd>13.38 m²\u003C\u002Ftd>\u003Ctd>158.4 sq ft\u003C\u002Ftd>\u003C\u002Ftr>\n\u003Ctr>\u003Ctd>20 × 15\u003C\u002Ftd>\u003Ctd>300 sq ft\u003C\u002Ftd>\u003Ctd>27.87 m²\u003C\u002Ftd>\u003Ctd>330 sq ft\u003C\u002Ftd>\u003C\u002Ftr>\n\u003Ctr>\u003Ctd>30 × 40\u003C\u002Ftd>\u003Ctd>1,200 sq ft\u003C\u002Ftd>\u003Ctd>111.48 m²\u003C\u002Ftd>\u003Ctd>1,320 sq ft\u003C\u002Ftd>\u003C\u002Ftr>\n\u003C\u002Ftbody>\n\u003C\u002Ftable>\n\u003Cp>Round dimensions in a listing are worth a tape measure of their own. A room advertised as 12 × 12 that measures 11.5 by 11.8 in reality gives \u003Cstrong>135.7 sq ft\u003C\u002Fstrong>, eight square feet short of the round figure and enough to move a tile order by one box.\u003C\u002Fp>\n\n\u003Ch2 id=\"square-meters-and-acres\">How is square footage converted to square meters or acres?\u003C\u002Fh2>\n\u003Cp>Metric tapes and European listings work in square meters, where one square meter holds \u003Cstrong>10.7639 sq ft\u003C\u002Fstrong>, so a 600 sq ft floor reads as \u003Cstrong>55.74 m²\u003C\u002Fstrong> while a 40 m² apartment reads as \u003Cstrong>430.56 sq ft\u003C\u002Fstrong>. Switching the Measured in field to meters keeps both readings on screen.\u003C\u002Fp>\n\u003Cp>One acre is \u003Cstrong>43,560 sq ft\u003C\u002Fstrong>, a figure inherited from the surveyor's chain of 66 ft, an acre being the strip of 66 ft by 660 ft that a team of oxen ploughed in a day. Past 4,000 sq ft the calculator adds the acre line, so a backyard of 100 × 60 shows as \u003Cstrong>6,000 sq ft and 0.138 acres\u003C\u002Fstrong>, the unit a plot listing quotes.\u003C\u002Fp>\n\n\u003Ch2 id=\"waste-allowance\">How much extra material should be ordered above the measured square footage?\u003C\u002Fh2>\n\u003Cp>Flooring is ordered above the measured area, \u003Cstrong>10%\u003C\u002Fstrong> above it on a straight-lay job, which turns \u003Cstrong>600 sq ft\u003C\u002Fstrong> of measured floor into \u003Cstrong>660 sq ft\u003C\u002Fstrong> of product. The order line runs that same calculation on any allowance from 0 to 50%.\u003C\u002Fp>\n\u003Cul>\u003Cli>\u003Cstrong>5 to 10%\u003C\u002Fstrong> for straight-lay plank or board, the share that covers the ends cut off each row and thrown away.\u003C\u002Fli>\u003Cli>\u003Cstrong>15%\u003C\u002Fstrong> for a diagonal or herringbone layout.\u003C\u002Fli>\u003Cli>\u003Cstrong>20%\u003C\u002Fstrong> for patterned tile that has to line up across a seam in a room with several doorways.\u003C\u002Fli>\u003C\u002Ful>\n\u003Cp>The leftover box then sits in a garage for years until a tile cracks and needs replacing. Dye lots, the production batches that tiles and planks come from, shift enough between runs that a fresh box rarely matches the floor already down. Tile and plank sell by the box in any case, so the counter rounds the order up to the next full box.\u003C\u002Fp>","2026-08-04T07:29:51.273Z","2026-08-07T10:00:02.662Z","2026-08-07T10:00:00.000Z","en","Square Footage Calculator",[16,20,24,28,32,36],{"id":17,"question":18,"answer":19},2180,"How do I calculate sq ft?","\u003Cp>Multiply the length by the width in feet. A room 14 ft long and 12 ft wide gives \u003Cstrong>168 sq ft\u003C\u002Fstrong>. For several rooms, work out each rectangle on its own then add the results, which is what happens above as soon as a second row is filled in.\u003C\u002Fp>\u003Cp>Two habits keep the total accurate on site.\u003C\u002Fp>\u003Cul>\u003Cli>Measure wall to wall at floor level, not at waist height where furniture forces a detour.\u003C\u002Fli>\u003Cli>Split any non-rectangular room into rectangles before measuring, one row per rectangle.\u003C\u002Fli>\u003C\u002Ful>",{"id":21,"question":22,"answer":23},2181,"How many sq ft is in a 12x12 room?","\u003Cp>A 12 by 12 room is \u003Cstrong>144 sq ft\u003C\u002Fstrong>, which converts to \u003Cstrong>13.38 m²\u003C\u002Fstrong>. That is the most common bedroom footprint in US listings.\u003C\u002Fp>\u003Cp>Ordering flooring for that room at the default 10% waste allowance means buying \u003Cstrong>158.4 sq ft\u003C\u002Fstrong>. Raise the allowance to 15% for a diagonal layout and the figure becomes \u003Cstrong>165.6 sq ft\u003C\u002Fstrong>, roughly one extra box on most plank formats.\u003C\u002Fp>",{"id":25,"question":26,"answer":27},2182,"How many sq ft is 30x40?","\u003Cp>A 30 by 40 area covers \u003Cstrong>1,200 sq ft\u003C\u002Fstrong>, the equivalent of \u003Cstrong>111.48 m²\u003C\u002Fstrong>. It stays under the 4,000 sq ft mark where the acre line appears, though the conversion still holds at \u003Cstrong>0.0275 acres\u003C\u002Fstrong>.\u003C\u002Fp>\u003Cp>That footprint is typical of a detached garage or a small shop unit. Poured as a slab 4 inches thick, the same 1,200 sq ft calls for \u003Cstrong>14.8 cubic yards\u003C\u002Fstrong> of concrete.\u003C\u002Fp>",{"id":29,"question":30,"answer":31},2183,"How many square feet is 8x8?","\u003Cp>An 8 by 8 space covers \u003Cstrong>64 sq ft\u003C\u002Fstrong>, the equivalent of \u003Cstrong>5.95 m²\u003C\u002Fstrong>. Dimensions at that scale come up for garden sheds, walk-in closets and small bathrooms.\u003C\u002Fp>\u003Cp>With the default 10% waste allowance the order figure is \u003Cstrong>70.4 sq ft\u003C\u002Fstrong>, which on most tile formats rounds up to one extra box beyond the bare 64 sq ft.\u003C\u002Fp>",{"id":33,"question":34,"answer":35},2184,"How is square footage calculated for a whole house?","\u003Cp>The square footage of a house is the sum of its finished floor areas, measured room by room. Five rooms of 22 × 18, 15 × 13, 16 × 14, 12 × 11 and 9 × 8 add up to \u003Cstrong>1,019 sq ft\u003C\u002Fstrong>, the living room alone taking 396 sq ft or \u003Cstrong>38.9%\u003C\u002Fstrong> of the total.\u003C\u002Fp>\u003Cp>US appraisers follow the \u003Cstrong>ANSI Z765\u003C\u002Fstrong> standard, which counts only finished space under a ceiling of at least \u003Cstrong>7 ft\u003C\u002Fstrong>. Under a sloped ceiling at least half the finished area has to reach that height, while nothing below \u003Cstrong>5 ft\u003C\u002Fstrong> counts at all. Three kinds of space stay out of the figure.\u003C\u002Fp>\u003Cul>\u003Cli>Garages, attached or not.\u003C\u002Fli>\u003Cli>Unfinished basements and crawl spaces.\u003C\u002Fli>\u003Cli>Open porches, decks and balconies.\u003C\u002Fli>\u003C\u002Ful>\u003Cp>A finished basement gets reported on its own line instead of joining the above-grade total, which explains part of the gap between a listing figure and an appraisal.\u003C\u002Fp>",{"id":37,"question":38,"answer":39},2185,"How many square feet are in an acre?","\u003Cp>One acre holds \u003Cstrong>43,560 sq ft\u003C\u002Fstrong>, which is \u003Cstrong>4,046.86 m²\u003C\u002Fstrong> or about 0.4047 hectare. The acre reading appears once the total passes \u003Cstrong>4,000 sq ft\u003C\u002Fstrong>, the point at which a measurement usually describes land instead of a floor plan.\u003C\u002Fp>\u003Cp>A lot of 100 ft by 60 ft then comes to 6,000 sq ft, which is \u003Cstrong>0.138 acre\u003C\u002Fstrong>. A quarter-acre plot, the familiar suburban unit, works out at \u003Cstrong>10,890 sq ft\u003C\u002Fstrong>.\u003C\u002Fp>",[],{"id":42,"documentId":43,"uid":44,"name":45,"tagline":46,"hubContent":47,"createdAt":48,"updatedAt":49,"publishedAt":50,"locale":13},27,"eb3vn4x2yjfb8rgjdmtb7r9e","home","Home & DIY","Materials, areas and layouts for home projects","\u003Cp>The calculators in this category answer the question that decides the order, which is how much material to buy. Concrete, gravel, mulch, tile, paint and lumber are each sold in their own unit, by the ton, the cubic yard, the box or the bag, so a raw volume rarely maps onto what a supplier will actually deliver. Every tool here turns a measurement into a purchase, adds the waste allowance the trade expects and flags the depths and dimensions that make a job fail.\u003C\u002Fp>","2026-08-04T07:29:26.689Z","2026-08-06T10:00:01.352Z","2026-08-06T10:00:00.000Z",{"id":52,"metaTitle":53,"metaDescription":54,"keywords":55,"metaRobots":55,"structuredData":55,"metaViewport":55,"canonicalURL":55},532,"Square Footage Calculator: Room by Room, Sq Ft & m²","Free square footage calculator for one room or a whole house. Room-by-room totals in sq ft, m² and acres, plus how much to order once waste is added.",null,[],[58,70,82,95],{"id":59,"documentId":60,"slug":61,"term":62,"definition":63,"relatedTools":64,"createdAt":67,"updatedAt":68,"publishedAt":69,"locale":13},17,"o1ljpluv6app6z9rrhst4gfn","cubic-yard","Cubic yard","\u003Cp>A \u003Cstrong>cubic yard\u003C\u002Fstrong> is the volume of a cube measuring 3 x 3 x 3 feet, which equals 27 cubic feet or about \u003Cstrong>0.7646 m³\u003C\u002Fstrong>. It is the standard unit for ordering bulk materials in the United States: ready-mix concrete, topsoil, gravel, sand and mulch are all priced and delivered by the cubic yard, often shortened to \"yard\" on a quote.\u003C\u002Fp>\u003Cp>For scale, a typical 12 x 10 ft patio slab poured 4 inches thick contains 40 cubic feet, which is 40 \u002F 27 = 1.48 cubic yards of concrete. A standard ready-mix truck carries 8 to 10 cubic yards, so that whole slab uses less than a fifth of one load.\u003C\u002Fp>\u003Cp>How big is a cubic yard in practice? The cube stands 3 feet on each side, roughly counter height, and holds about 14 full wheelbarrow loads of material. Spread out, one cubic yard covers close to 100 square feet at a depth of 3 inches, the usual layer for mulch or a gravel path.\u003C\u002Fp>",[65,66],"math\u002Fconcrete-calculator","math\u002Fvolume-calculator","2026-07-18T14:23:56.812Z","2026-08-02T10:00:01.228Z","2026-08-02T10:00:00.000Z",{"id":71,"documentId":72,"slug":73,"term":74,"definition":75,"relatedTools":76,"createdAt":79,"updatedAt":80,"publishedAt":81,"locale":13},16,"mdw0ypy9f3z1nioxaxnl9rvr","password-entropy","Entropy (passwords)","\u003Cp>\u003Cstrong>Entropy\u003C\u002Fstrong> measures how unpredictable a password is, expressed in bits. Each additional bit doubles the number of guesses an attacker needs. For a randomly generated password, it follows a simple formula: entropy = length × log2 of the alphabet size, so both the length and the variety of characters raise the score.\u003C\u002Fp>\u003Cp>A random 16-character password drawn from the 94 printable ASCII symbols reaches 16 × log2(94), about \u003Cstrong>105 bits\u003C\u002Fstrong>. At 10 billion guesses per second, exhausting that space would take on the order of 10^14 years, while a 6-character password from the same alphabet peaks at 39 bits and falls in about a minute.\u003C\u002Fp>\u003Cp>Written as a formula, \u003Cstrong>E = L × log2(N)\u003C\u002Fstrong>: the entropy equals the length L multiplied by the base-2 logarithm of N, the number of possible symbols per character. Current guidance treats 75 to 80 bits as the comfortable minimum for accounts that matter, a level a random 12-character password mixing all character types already clears.\u003C\u002Fp>",[77,78],"generator\u002Fpassword-generator","generator\u002Fusername-generator","2026-07-18T14:23:55.755Z","2026-08-01T10:00:01.360Z","2026-08-01T10:00:00.000Z",{"id":83,"documentId":84,"slug":85,"term":86,"definition":87,"relatedTools":88,"createdAt":92,"updatedAt":93,"publishedAt":94,"locale":13},15,"ypkfs6wnfljm03ge2b1ztiwv","percentage-point","Percentage point","\u003Cp>A \u003Cstrong>percentage point\u003C\u002Fstrong> is the unit used to express the arithmetic difference between two percentages. It compares rates by subtraction, while \"percent\" compares them by division: the two measures answer different questions and can differ wildly for the same change.\u003C\u002Fp>\u003Cp>Example: an interest rate that moves from 5% to 7% rises by \u003Cstrong>2 percentage points\u003C\u002Fstrong> (7 - 5 = 2), but by 40 percent in relative terms (2 ÷ 5 × 100 = 40). Saying \"the rate went up 2%\" would be wrong on both counts: the correct phrasings are \"up 2 points\" or \"up 40%\".\u003C\u002Fp>\u003Cp>The standard abbreviation is \u003Cstrong>pp\u003C\u002Fstrong>, sometimes just \"points\", as in \"unemployment fell by 0.5 pp\". Confusing percent with percentage points remains the classic trap: a party moving from 20% to 30% in the polls gains 10 percentage points, yet grows by 50 percent, and headlines regularly pick the wrong figure.\u003C\u002Fp>",[89,90,91],"math\u002Fpercentage-calculator","math\u002Faverage-calculator","finance\u002Fcalcul-remise","2026-07-18T14:23:54.573Z","2026-07-31T10:00:01.940Z","2026-07-31T10:00:00.000Z",{"id":96,"documentId":97,"slug":98,"term":99,"definition":100,"relatedTools":101,"createdAt":104,"updatedAt":105,"publishedAt":106,"locale":13},14,"g3okb797ekrz0kkpm36mfjwc","weighted-average","Weighted average","\u003Cp>A \u003Cstrong>weighted average\u003C\u002Fstrong> is an average where each value counts in proportion to an assigned importance, called its weight, instead of counting equally. Each value is multiplied by its weight, the products are added, and the sum is divided by the total of the weights. Class grades, GPAs, and stock indexes are all weighted averages.\u003C\u002Fp>\u003Cp>Example: scores of 92, 85, and 88 with weights of 30, 30, and 40 give (92 x 30 + 85 x 30 + 88 x 40) \u002F 100 = \u003Cstrong>88.3\u003C\u002Fstrong>. The plain average of the same scores is 88.33, but if the heaviest score dropped to 78, the weighted average would fall to 84.3 while the plain average only fell to 85.\u003C\u002Fp>\u003Cp>The weighted average formula in plain words: multiply each value by its weight, add up the products, then divide by the sum of the weights. In a spreadsheet the whole calculation fits in one cell, since Excel's SUMPRODUCT function multiplies and adds in a single pass: SUMPRODUCT of the values and weights, divided by SUM of the weights.\u003C\u002Fp>",[90,102,103],"math\u002Fgrade-calculator","math\u002Fgpa-calculator","2026-07-18T14:23:53.329Z","2026-07-30T10:00:01.216Z","2026-07-30T10:00:00.000Z",{"slugs":108},[109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,6,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,162,163],"age-calculator","average-calculator","cd-calculator","concrete-calculator","cursive-font-generator","date-calculator","fantasy-name-generator","final-grade-calculator","fraction-calculator","glitch-text-generator","gpa-calculator","grade-calculator","hex-converter","hours-calculator","interest-calculator","military-time-converter","roman-numeral-converter","password-generator","binary-converter","celsius-to-fahrenheit-converter","kg-to-lbs-converter","percentage-calculator","word-counter","tip-calculator","morse-code-translator","username-generator","ratio-calculator","sales-tax-calculator","small-text-generator","mm-to-inches-converter","volume-calculator","timer","stair-calculator","roof-pitch-calculator","board-foot-calculator","aspect-ratio-calculator","rounding-calculator","random-letter-generator","mulch-calculator","fence-calculator","upside-down-text-generator","acreage-calculator","gravel-calculator","proportion-calculator","paint-calculator","tile-calculator","braille-translator","quadratic-formula-calculator","gcf-calculator","probability-calculator","hex-to-rgb-converter","uuid-generator","standard-deviation-calculator","lcm-calculator","caesar-cipher"]