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Business documents

Invoice Generator

Create a professional invoice with taxes, discounts and your logo, then download it as PDF or print it.

Quote Generator

Prepare a clear quote or estimate for your client, with validity date, taxes and totals, ready as PDF.

Tax

VAT Calculator

Add or remove VAT from any amount and see the net price, the tax and the gross price instantly.

Pricing & profit

Profit Margin Calculator

Find your profit and margin from cost and price, or the price you need for a target margin.

Markup Calculator

Turn a cost into a selling price with a markup percentage or multiplier, and see the resulting margin.

Discount Calculator

See the final price and the amount saved after one or two successive discounts.

Break-Even Calculator

Find how many units and how much revenue you need to cover your fixed and variable costs.

Freelance & sales

Commission Calculator

Calculate a sales commission with a flat rate or tiered rates, and the amount left after commission.

Everyday maths

Percentage Calculator

Percent of a number, what percent one number is of another, and percentage increase or decrease.

BUILNORA

BUILNORA — tools for construction

Quantities for concrete, blocks and bricks, rebar, screed, paint and tiles, with waste margins built in, for professionals and serious DIY.

BUILNORA

Concrete Calculator

Volume of concrete for slabs, footings and columns, with waste margin and cement, sand and gravel quantities.

BUILNORA

Paint Calculator

How much paint you need for your walls and ceilings, minus doors and windows, for the number of coats you plan.

BUILNORA

Tile Calculator

Number of tiles and boxes for a floor or wall, with grout joints and a cutting waste margin.

BUILNORA

Block & Brick Calculator

Blocks or bricks, mortar and cement bags for a wall, with openings deducted and a breakage margin.

BUILNORA

Rebar Weight Calculator

Weight of reinforcing steel from diameter and length, laps included, and the 12 m bars to buy.

BUILNORA

Screed Calculator

Volume of floor screed and the cement bags, sand and water needed for your area and thickness.

Open BUILNORA

Why PRAXAO

Free and unlimited

Every tool is free to use as often as you need. No sign-up, no trial, no watermark.

Exact calculations

Amounts are computed with exact decimal arithmetic and correct rounding for each currency.

Private by design

Your figures are calculated in your browser. We do not sell data and collect only anonymous usage statistics.

Five languages

English, French, Spanish, German and Arabic, with localized numbers, currencies and documents.