A date calculator can answer two different questions: how many calendar days separate two dates, or which date falls a chosen number of days before or after a starting date. To get a meaningful answer, define the counting convention before comparing results. Calendar days include weekends and holidays. Business-day calculations exclude days according to a work calendar, so they are a separate task. This guide explains date arithmetic using calendar days and date-only values rather than elapsed hours between timestamps. Use the Date Calculator to compare elapsed and inclusive counts or add and subtract calendar days. Calculate elapsed days between two dates The elapsed calendar-day difference treats the starting date as day zero. From November 2 to November 6, 2026, the difference is four days. From November 2 to November 2, the difference is zero days. That convention measures the distance between the dates. It does not count every labeled date touched by the range. If you...

  To calculate business days between two dates, decide which weekdays count as working days, whether the start and end dates are included, and which holidays or closures must be excluded. Without those choices, two correct calculations can give different answers for the same dates. This guide uses a Monday-to-Friday schedule for its examples. That is an illustrative convention, not a calendar that applies to every employer, service, or country. A business-day calculator should make these assumptions visible rather than silently treating every weekday as a working day. Use the Business Days Calculator to count workdays with your chosen excluded weekdays, closure dates, and boundary settings. 1. Define your working week Start with the days that are normally eligible. For a Monday-to-Friday schedule, Saturday and Sunday are excluded. A business operating on Saturday or using another weekly closure pattern needs a different calendar. Personal leave, company shutdowns, and public h...

  To calculate board feet of lumber, multiply thickness in inches by width in inches and length in feet, divide by 12, then multiply by the number of pieces. Add the volumes of separate lots before multiplying by a shared price per board foot. Use the Board Foot Calculator for up to four lots. It calculates the volume represented by your entered dimensions. It does not determine a cutting list, convert nominal sizes automatically, or predict how much usable lumber a log will yield. What is a board foot? One board foot equals 144 cubic inches. Imagine a rectangular piece 1 inch thick, 12 inches wide, and 12 inches long: that piece contains one board foot. The unit measures volume, even though its name can sound like a length measurement. Because a cubic foot contains 1,728 cubic inches, it contains 12 board feet. One board foot also equals exactly 0.002359737216 cubic meters. These conversions describe geometric volume, not supplier tally rules or the amount of finished materia...

  To calculate one straight stair flight, divide the finished total rise by your chosen number of equal risers. With the upper landing serving as the final walking surface, there is one fewer separate tread than risers. Multiply the separate tread count by horizontal going to find the tread run. Use the Stair Calculator to compare these measurements. It calculates geometry from your inputs, not a ready-to-cut stringer pattern or an automatically approved stair design. Measure the finished total rise Total rise is the vertical difference between the finished lower walking surface and the finished upper landing. Use the levels that the completed staircase must connect. Measuring unfinished framing without accounting for the intended finishes can change the first or last riser in the assembled stair. Enter all dimensions in the selected unit. In inches mode, 7 feet is 84 inches. Do not enter a feet-and-inches expression as a decimal: 7 ft 6 in is 90 inches, not 7.6 inches. Metric...

  To calculate pool volume, multiply the water surface area by the actual water depth. For a flat-bottom above-ground pool, choose the formula matching its inside shape, then convert the result to US gallons or liters. Use the Pool Volume Calculator 1. Measure the water, not the outside frame Measure inside length and width at the waterline. For a circle, measure inside diameter. Use actual filled water depth, not wall height or a nominal pool model size. This method assumes vertical sides and a flat bottom of constant depth. 2. Choose the correct area formula Rectangle: length x width. Circle: pi x diameter squared / 4. True ellipse: pi x overall length x overall width / 4. Oblong with two semicircular ends: (overall length - width) x width + pi x width squared / 4. An ellipse is different from an oblong. For irregular outlines or other oval shapes, do not assume either formula fits; consult manufacturer data or measure separate sections. 3. Use consistent depth units When area is...

  To calculate square footage for siding, add rectangular wall areas and triangular gable areas, then subtract doors and windows. Use the net area with manufacturer installed coverage to estimate whole purchase units. Use the Siding Calculator 1. Measure rectangular walls Multiply width by height. A 20 ft wide wall with a height of 8 ft has 160 sq ft of gross area. Measure each separate section without counting the same area twice. 2. Calculate gable area For a triangular gable, multiply base width by perpendicular height and divide by two. A 20 ft wide gable with a 4 ft rise has 40 sq ft of area. The rise is not the sloping edge length. Treat other shapes as separate measured sections. 3. Subtract openings Deduct the measured area of doors and windows from the corresponding section. In this example, 20 sq ft of openings in the rectangular wall leaves 140 sq ft. Adding the separate 40 sq ft gable gives 180 sq ft net siding area. 4. Add your chosen allowance Multiply net area by (1 ...

  To calculate pool volume, multiply the water surface area by the actual water depth. For a flat-bottom above-ground pool, choose the formula matching its inside shape, then convert the result to US gallons or liters. Use the Pool Volume Calculator 1. Measure the water, not the outside frame Measure inside length and width at the waterline. For a circle, measure inside diameter. Use actual filled water depth, not wall height or a nominal pool model size. This method assumes vertical sides and a flat bottom of constant depth. 2. Choose the correct area formula Rectangle: length x width. Circle: pi x diameter squared / 4. True ellipse: pi x overall length x overall width / 4. Oblong with two semicircular ends: (overall length - width) x width + pi x width squared / 4. An ellipse is different from an oblong. For irregular outlines or other oval shapes, do not assume either formula fits; consult manufacturer data or measure separate sections. 3. Use consistent depth units When area is...

  To calculate square footage for siding, add rectangular wall areas and triangular gable areas, then subtract doors and windows. Use the net area with manufacturer installed coverage to estimate whole purchase units. Use the Siding Calculator 1. Measure rectangular walls Multiply width by height. A 20 ft wide wall with a height of 8 ft has 160 sq ft of gross area. Measure each separate section without counting the same area twice. 2. Calculate gable area For a triangular gable, multiply base width by perpendicular height and divide by two. A 20 ft wide gable with a 4 ft rise has 40 sq ft of area. The rise is not the sloping edge length. Treat other shapes as separate measured sections. 3. Subtract openings Deduct the measured area of doors and windows from the corresponding section. In this example, 20 sq ft of openings in the rectangular wall leaves 140 sq ft. Adding the separate 40 sq ft gable gives 180 sq ft net siding area. 4. Add your chosen allowance Multiply net area by (1 ...

  Calculate block fill volume by multiplying the number of installed blocks being filled by manufacturer fill volume per block. Add a chosen allowance, then convert volume or estimate whole bags using the specified product yield. Use the Concrete Block Fill Calculator 1. Count the blocks actually being filled Use installed blocks for the specified filled-cell configuration. Do not include spare blocks purchased for cuts or breakage. Calculate different block types, bond beams, and configurations separately. 2. Find manufacturer fill volume Use the fill table for the actual block and configuration. Nominal outside dimensions such as 8 x 8 x 16 inches do not determine internal void volume. If no matching data is available, ask the supplier rather than assuming a universal capacity. 3. Calculate adjusted volume Fill volume = block count x fill volume per block. Multiply by (1 + allowance / 100) for your chosen extra allowance. For an illustrative 100 blocks at 0.12 cu ft each, net vol...

  Calculate bricks for one wall face by subtracting openings from gross wall area, multiplying by the manufacturer brick count per unit area, adding your chosen allowance, and rounding up. Use the Brick Calculator 1. Measure the wall and its openings Multiply wall length by height. A 20 ft by 8 ft wall has 160 sq ft of gross area. Subtract 20 sq ft of doors and windows to get 140 sq ft. Do not subtract openings twice if using a net measured area. 2. Check manufacturer installed coverage Use the stated brick count per sq ft or sq m for the actual product, visible face, orientation, bond, and joint size. There is no single correct rate for all bricks. Multiple wall layers and structural thickness need separate design. 3. Add allowance and round bricks Required bricks = round up [net wall area x manufacturer brick count per area x (1 + allowance / 100)]. At an illustrative 7 bricks per sq ft, 140 sq ft and 10% allowance give 1,078 bricks. This rate and allowance are examples, not reco...

  To calculate pavers for a patio, divide the adjusted net installation area by the supplier's installed coverage per purchase unit, then round up to a whole unit. Use the Paver Patio Calculator 1. Measure net patio area For a rectangular 12 ft by 10 ft patio, multiply 12 by 10 to get 120 sq ft. Add separate sections and subtract areas that will not receive pavers. Keep units consistent. 2. Match your purchase unit Check whether you buy individual pavers, packs, or pallets. Use coverage and price for that same unit. For mixed-size patterns, use coverage for the manufacturer's complete assortment rather than a single nominal piece size. 3. Add your chosen allowance Adjusted area = net area x (1 + allowance / 100). A 10% illustrative allowance increases 120 sq ft to 132 sq ft. The appropriate allowance depends on cuts, layout, and project conditions. 4. Round up packs and calculate cost At 20 sq ft per pack, 132 / 20 = 6.6, so purchase 7 whole packs. If each contains 40 pieces, p...

  To estimate tile grout bags or tubs, use the manufacturer's coverage for your exact grout, package size, tile dimensions, joint width, and joint depth. Divide the net tiled installation area including your chosen allowance by that coverage and round up to whole purchased packs. The Grout Calculator for Tile Coverage and Packs lets you enter a single coverage value or compare the minimum and maximum coverage of a product's applicable range. It does not assume a universal grout density. 1. Identify the tiled installation area Enter the actual floor and wall areas being grouted, after removing untiled openings. Use the area of the tiled surface, not just the narrow strips between tiles. Manufacturer coverage charts normally relate package consumption to a tiled surface with a specified tile-and-joint configuration; follow the chart's own instructions. Do not replace the installation area with the coverage of all purchased tile boxes. Extra tiles bought for cuts or spares d...

  To estimate thinset bags, divide the net installation area including your chosen material allowance by the applicable coverage per bag, then round up. Use coverage from the exact mortar manufacturer's guidance for your product, bag size, and installation conditions. The Thinset Calculator adds separate floor, wall, and other installation areas. You can enter one coverage value or a coverage range to compare whole-bag scenarios. It does not select mortar, a trowel, or an installation method. 1. Measure the area receiving mortar For a rectangular section, area equals length x width. Add only the surfaces receiving the same mortar under matching application conditions. Subtract openings before entering net wall area and avoid counting overlapping sections twice. A 120 sq ft floor and 80 sq ft of wall tile installation total 200 sq ft. If the wall application requires a different product or coverage rate, calculate it separately instead of combining those areas. 2. Find the approp...

  To estimate composite decking surface boards, measure the area to cover, calculate the area of one actual board, add your chosen material allowance, and round the result up to whole boards. Build a budget from your own board price and quotes for the rest of the work. The Composite Decking Cost Calculator accepts rectangular dimensions or a known surface area. Its board count is based on area, not a board-by-board cutting layout or a structural design. 1. Measure the deck surface For a rectangle, area = length x width. A 12 ft by 10 ft surface has an area of 120 sq ft. For an irregular shape, measure its non-overlapping sections separately, add their areas, and use known-area mode. Stairs, borders, or additional platforms may need separate calculations. 2. Use actual board dimensions Board area equals actual length x actual width in matching units. For US measurements, divide width in inches by 12 to convert it to feet. A 12 ft board that is 5.5 inches wide covers 12 x (5.5 / 1...

  To estimate wall insulation packs, measure each wall, subtract the area of its doors and windows, add the net areas, apply your chosen material allowance, and divide by the coverage of the pack you will buy. Round up to whole purchased packs. The Wall Insulation Calculator combines up to five rectangular walls using the same insulation product. It estimates area-based quantities and optional pack cost; it does not select thermal performance or design an insulation assembly. 1. Measure the gross area of each wall For a rectangle, gross wall area equals length x height. A 12 ft long wall with an 8 ft height has 96 sq ft of gross area. A second wall measuring 10 x 8 ft has 80 sq ft. Together they have 176 sq ft before subtracting openings. Use only the walls or sections you plan to insulate. Do not automatically count every interior partition or double count shared sections. Divide irregular surfaces into non-overlapping rectangular zones where appropriate. 2. Subtract doors and ...

  To calculate vinyl plank flooring for several rooms, measure the floor area in each room, add the areas, apply your chosen waste allowance, divide by coverage per box, and round up to whole boxes. Only pool rooms that will use the same product. Use the Vinyl Plank Flooring Calculator for Multiple Rooms to combine up to five rectangular rooms or zones and optionally calculate a budget from your own box price and installation quote. 1. Measure each room or rectangular zone For a rectangle, floor area equals length x width. A 12 ft by 10 ft room is 120 sq ft. A 10 ft by 8 ft room is 80 sq ft. Together, they total 200 sq ft. For irregular rooms, divide the floor into non-overlapping rectangles, then enter each zone separately. Avoid counting shared or overlapping sections twice. Use either feet for all dimensions and square feet for box coverage, or meters and square meters throughout. Do not mix units. The calculator clears dimensions and box coverage when measurement systems chan...

  A small bathroom remodel budget combines measured material quantities with prices for fixtures, labor, and other work. Room size alone does not determine the total: the scope, location, products, condition of the room, and contractor quotes also matter. Use the Small Bathroom Remodel Cost & Materials Calculator to estimate floor and wall tile boxes, then add your own equipment prices and work estimates. The calculator does not supply average local remodeling prices. 1. Measure the areas you will actually tile For a rectangular floor, multiply length by width. Measure only the wall sections selected for tile, rather than assuming every wall will be fully tiled. Subtract the area of doors or windows only when those openings fall inside the selected tile area. Floor and wall areas remain separate because the products and box coverage can differ. Irregular shapes require measurements of their individual sections. The calculator accepts a known area; it does not generate a t...

  To estimate drywall for a flat ceiling, multiply its length by its width, add your chosen waste allowance, divide by the area of one sheet, and round up. For room walls, first calculate their gross surface area and subtract the wall openings you choose to exclude. The Drywall Calculator for Walls and Ceilings lets you calculate a rectangular room, a ceiling alone, or a known surface area. It estimates sheet quantities from your inputs, not a cutting layout or an installation specification. How to calculate drywall for a ceiling For a flat rectangular ceiling: Ceiling area = room length x room width A 12 ft by 10 ft ceiling has an area of 120 sq ft. A 4 ft by 8 ft sheet covers 32 sq ft before cuts. At 0% waste, 120 / 32 = 3.75, which rounds up to 4 sheets. With an illustrative 10% allowance, 120 x 1.10 / 32 = 4.125, which rounds up to 5 sheets. The allowance is your choice. It is not a guarantee that all cuts will fit or that a particular percentage is appropriate. Joint p...

  A kitchen remodel budget starts with a list of costs and a clear distinction between estimates and payments. Use the Kitchen Remodel Budget Calculator to add your own estimates and a contingency reserve. 1. Collect estimates for each part of the project List cabinets and hardware, countertops, appliances, installation, plumbing and electrical work, flooring and backsplash, permits, and other costs. Include delivery, tax, and disposal if your quotes exclude them. Do not count materials twice when installation quotes already include them. 2. Add the project subtotal For example, cabinets of $7,000, countertops of $3,000, appliances of $3,000, labor of $4,000, plumbing and electrical of $1,500, flooring of $1,000, and permits and other costs of $500 add up to $20,000. These are arithmetic examples, not typical US prices. 3. Set a contingency reserve At 15%, a $20,000 subtotal has a $3,000 reserve and a $23,000 total planned budget. Choose a percentage appropriate to your project an...

  To calculate a fixed auto loan payment, you need the amount financed, the interest rate, and the number of monthly payments. The vehicle price alone does not tell you how much you will borrow or repay. Use the Auto Loan Payment Calculator for a fully amortizing fixed-rate monthly illustration. Step 1: find the amount financed Use the actual loan amount from the offer where available. A down payment reduces borrowing. A trade-in and any loan attached to it need to be accounted for, and taxes or fees may be paid upfront or financed. This tool does not assume a local tax rate or trade-in credit rule. Step 2: convert the interest rate The formula uses a nominal annual interest rate, converted to a monthly decimal rate. At 6% per year, the monthly rate is 0.06 / 12 = 0.005 . APR may include fees and differ from this rate, so do not assume the two always produce the same payment. Step 3: enter the term in months For a five-year loan with monthly payments, N is 60. This model assumes t...

  To work out how much rent fits a budget, start with take-home income and subtract the other commitments that money must cover. A remaining balance is useful for planning, but it does not establish a universally affordable rent or a landlord's approval. Use the Rent Affordability Calculator to test your own monthly amounts. Step 1: use monthly take-home income Use income available after taxes and payroll deductions. Do not mix an annual salary with monthly expenses or treat gross pay as take-home pay. If income varies, compare several realistic months and consider how you would handle a lower-income period. Step 2: list non-rent commitments Include living expenses such as food, transport, healthcare, childcare, and recurring bills. Add debt payments and planned savings or reserves separately. Include costs associated with the rental that are not part of rent, such as utilities, insurance, or parking where applicable. Count each item once. If retirement or insurance payments were ...