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Home & DIY Β· 52 Free Tools

Home & DIY Tools

Precision calculators and guides for paint coverage, tiling area, concrete volume, timber sizing, and electrical wiring. Practical mathematics for home improvement and construction.

All 52 Home & DIY Calculators & Utilities

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  • 🧴 Adhesive Selector β€” Which Glue Sticks This to That?

    Pick the two things you are joining and the conditions it has to survive, and this works out which adhesive will actually hold β€” with open time, clamp time, full cure and the surface prep that make...

  • πŸͺ΅ Board-Foot Lumber Calculator

    A board foot is 1" Γ— 12" Γ— 12". Enter the dimensions of your boards and the quantity, and get the board footage, linear footage and cost.

  • 🧱 Brick Calculator

    Calculate how many bricks you need for any wall β€” including mortar joints, waste, and pallets to order. Works for UK standard, metric, and imperial bricks.

  • πŸš— Car Care & MOT Due-Date Tracker

    Keeps the dates that are easy to miss and expensive to miss in one place: MOT, tax, insurance, service intervals, and the four items that actually cause MOT failures. Saved in your browser only β€” n...

  • 🌱 Compost Carbon:Nitrogen Balancer

    Slimy and smelly means too much nitrogen; dry and stubborn means too much carbon. Tell it what’s gone into the heap and it estimates your C:N ratio and exactly what to add next.

  • 🧱 Concrete Mix Calculator

    Calculate cement, sand, gravel, and water for any concrete project β€” from fence posts to shed bases.

  • Curtain Width & Drop Calculator

    Work out the width needed per curtain panel and the finished drop, with optional hem and heading allowances for homemade curtains.

  • πŸ’§ Damp & Mould Diagnostic (UK homes)

    Answer a few questions about the damp patches, mould and smells in your home and get the most likely cause β€” condensation, penetrating damp, rising damp or a leak β€” with the practical fixes and whe...

  • πŸͺ΅ Deck Joist Span & Footing Calculator

    Check how far a joist can safely span: pick the lumber size, spacing, wood type and load, and get the maximum span plus the beam and post spacing to match.

  • πŸͺ΅ Decking Calculator

    Calculate boards, joists, posts, screws, and total cost for a timber decking project. Works for softwood, hardwood, and composite decking.

  • πŸ’‘ Downlight Spacing Calculator

    A common rule is spacing β‰ˆ 0.5–0.75 Γ— ceiling height, with the first lamp about half that from the wall. Check beam angle and joists β€” this is a layout sketch, not a lighting design.

  • 🧱 Drywall (Plasterboard) Calculator

    Order the right amount of board: enter the wall and ceiling area, pick a sheet size and wastage, and get the sheet count plus the joint compound, tape and screws to finish it.

  • πŸ—οΈ Fence Calculator

    Calculate posts, panels, gravel boards, concrete, and total cost for a garden fence. Works for panel fencing, closeboard, and picket styles.

  • 🌱 Plant Spacing Calculator

    How many plants fit a bed at a given spacing. Square grid is simplest; triangular (hex) packing fits about 15% more. Leave paths out of the length and width.

  • πŸͺ¨ Gravel & Aggregate Calculator

    Calculate how much gravel, slate, chippings, or aggregate you need for driveways, paths, patios, or garden beds. Includes tonnes, bulk bags, and cost.

  • 🧱 Grout & Tile Adhesive Calculator

    The tiles are one thing β€” the grout and adhesive to fix them are another. Enter the tiled area, tile size and joint width to work out how much grout and thinset to mix.

  • 🏠 Home Inventory & Insurance Worksheet

    Create a clear room-by-room record of belongings, quantities, serial numbers and replacement values for a move or an insurance review. Add, search, export, and re-import a JSON backup. Entries stay...

  • 🏠 Home Maintenance Planner & Service Log

    Keep routine home jobs, appliance servicing and the last-completed dates together. Sort upcoming work, log a completion, and export a backup or spreadsheet-friendly service log. It saves in this br...

  • 🧾 Home Project Quote Comparator

    Compare up to three contractor estimates on a more like-for-like basis. Record each quote’s total, known extras, included work, exclusions, schedule, payment terms and guarantee notesβ€”without prete...

  • 🧊 Insulation Savings Calculator

    Estimate how much you could save by insulating your loft, walls, or floor. Based on UK energy prices.

  • πŸͺ΅ Laminate Flooring Calculator

    Work out how many packs of laminate to buy: enter the room, the plank size, planks per pack and pack price, and this adds the wastage so you don't run short mid-lay.

  • πŸ›οΈ Mattress Size Converter

    UK, US and EU bed names are not the same size. A UK king is 150 Γ— 200 cm; a US king is 193 Γ— 203 cm. Fitted sheets do not stretch that gap. Depth (deep-fitted) is separate.

  • 🌱 Micro Garden: Grow Food With No Land

    Turn a balcony, windowsill or tiny yard into real food. Tell it your space, sun and season and it ranks what to grow by calories per square metre β€” with a sowing calendar, harvest forecast and mone...

  • πŸ“ Miter & Bevel Angle Calculator

    Set the saw for a perfect corner: enter the corner angle and pick flat or crown molding, and get the miter and bevel angles to dial in.

  • πŸ“¦ Moving House Box & Supplies Estimator

    Everyone under-buys boxes by half. Tell it the size of the place, the people in it and how long you’ve been there β€” get a realistic shopping list plus the packing timeline removal crews wish everyo...

  • πŸ‚ Mulch Coverage Calculator

    Volume = area Γ— depth. A 50 litre bag is 0.05 mΒ³. Bark mulch is usually 5–8 cm; paths can be 10 cm. Order a little extra for settling β€” bags are sold by loose volume.

  • πŸ‘‚ Mystery Hum & Whine Identifier

    That low hum at night, a whine from the walls, a buzz nobody else hears. Record it with your microphone and this finds the dominant pitches and matches them to likely sources: mains electricity (50...

  • 🎨 Paint Calculator

    Calculate exactly how much paint you need for any room. No more buying 5 tins for a cupboard.

  • πŸ–ΌοΈ Picture Hanging Calculator

    Calculate the perfect height and hook position so your pictures hang straight and look professional.

  • πŸͺ£ Plastering Calculator

    Calculate how much plaster, render, or screed you need for walls, ceilings, or floors. Includes bags, coverage, and estimated cost.

  • πŸ”§ Pipe Sizing Guide

    Look up the right pipe diameter for any domestic plumbing job. Covers hot/cold water, central heating, and waste.

  • 🏊 Pool & Spa Volume

    Litres and gallons from length, width and average depth. Rectangular, circular and oval. Chemical dosing is per 1,000 litres β€” this is volume only, not a treatment plan.

  • πŸ“½οΈ Projector Throw Distance

    Throw ratio = distance to screen Γ· image width. A 1.5:1 lens 3 m from the wall makes a 2 m wide picture. 16:9 assumed unless you change it. Check the projector’s own min/max zoom range.

  • 🌧️ Rainwater Harvest

    1 mm of rain on 1 mΒ² is 1 litre. Multiply by a runoff coefficient (tiles ~0.85, felt ~0.8). UK roofs often yield more than a water-butt can hold β€” size the tank, not just the dream.

  • 🏠 Rental Move-in Condition Report

    Make a room-by-room check-in record while details are fresh. Note meter readings, keys, visible wear or damage, things not tested, and photo references. Entries stay in this page until you copy or ...

  • Repair CafΓ© Coordinator

    Plan a repair event around the skills and hours people actually offer. Match repair requests to volunteers, show the waiting list, and calculate the proposed workload without promising a repair wil...

  • πŸ”§ Repair or Replace?

    The throwaway economy wants you to bin it and buy another. This decider weighs the three things that actually matter β€” cost per useful year, embodied carbon and remaining life β€” and tells you hones...

  • 🏠 Roof Pitch & Rafter Calculator

    Roof pitch is the rise in inches for every 12" of run. Enter the pitch and half-span (run), and get the rafter length, angle and roof-area multiplier.

  • 🌑️ Room BTU & HVAC Sizing Calculator

    Estimate the heating and cooling load for a room: area, ceiling height, insulation, sun exposure, occupancy and climate all move the number of BTUs you need.

  • πŸ›‹οΈ Room Layout Planner

    Drag and drop furniture to plan your room layout. Scale-accurate 2D top-down view.

  • Scale Drawing Converter

    Convert plan measurements to real dimensions or real dimensions to a drawing, with explicit units and a photocopy enlargement or reduction factor.

  • πŸ”© Screw & Drill Bit Size Chart

    Look up the right drill bit for any screw size, wall plug colour, and pilot hole diameter. No more guessing.

  • πŸ“ Shelf Bracket Calculator

    Calculate the right bracket size, spacing, and load capacity for your shelf project.

  • πŸ—‘οΈ Skip Hire Volume Calculator

    Rough cubic yards from room waste, rubble or bags. UK skips are sold in yards: 4, 6, 8, 12, 16. Loose waste settles; rubble is heavy β€” many yards cap weight before the skip looks full. Not a quote.

  • πŸͺœ Stair Stringer Calculator

    Size a straight staircase: enter the total rise and your preferred riser height, and get the number of steps, the tread depth, total run and the stair angle β€” checked against the comfortable 2Γ—rise...

  • 🧱 Stud & Wall Framing Calculator

    Frame a wall the way a carpenter would: enter the wall length, stud spacing, openings and corners, and get the stud count, plate lumber and headers to order.

  • Surplus Materials Exchange

    Give spare materials another useful life: match community projects to offered quantities, keep units consistent, and show leftovers and unmet needs before arranging collection.

  • 🧱 Tile & Flooring Estimator

    Calculate tiles, planks, or carpet needed for any room β€” including waste and cuts.

  • πŸ“Ί TV Viewing Distance Calculator

    Recommend a sofa distance from screen diagonal and resolution. Uses SMPTE 30Β° field-of-view, THX 40Β°, and a sharpness seat where 4K/1080p pixels sit at about 1 arc-minute. Advice, not a living-room...

  • πŸ”© Wall Anchor Selector

    Not sure what fixings to use? Tell us your wall type and what you're hanging β€” we'll tell you exactly what to buy.

  • 🧻 Wallpaper Estimator

    Calculate how many rolls of wallpaper you need β€” accounting for pattern repeat, doors, and windows.

  • πŸ›‹οΈ Will It Fit? Sofa & Furniture Path Checker

    Checks the whole route, not one door: a doorway, the tilt-and-pivot through it, then a 90Β° hallway corner β€” the place sofas actually get stuck. Uses the real geometry of a box turning a corner and ...

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