# Free calculators for contractors and small business Free online calculators for contractors and small businesses. Profit margin, HVAC CFM, roof pitch, decking, and more. Fast, accurate results. Canonical page: https://invoicemama.com/calculators ## Calculators - [HVAC CFM Calculator](https://invoicemama.com/calculators/hvac-cfm-calculator): Calculate the exact airflow (CFM) your room needs for optimal ventilation and comfort. - [Roof Pitch Calculator](https://invoicemama.com/calculators/roof-pitch-calculator): Calculate roof pitch from rise and run. Convert between degrees, percentage, radians, and x:12 ratio instantly. - [Decking Calculator](https://invoicemama.com/calculators/decking-calculator): Calculate exactly how many deck boards, linear feet, and screws you need for your project. - [Profit Margin Calculator](https://invoicemama.com/calculators/profit-margin-calculator): Calculate your true profit margin instantly. Enter your revenue and costs to see exactly what you keep from every job. - [Labor Cost Calculator](https://invoicemama.com/calculators/labor-cost-calculator): Calculate your true labor costs including wages, taxes, benefits, and overhead. Know exactly what to charge per hour. - [House Cleaning Cost Calculator](https://invoicemama.com/calculators/house-cleaning-cost-calculator): Calculate competitive pricing for residential cleaning jobs based on home size, cleaning type, and add-on services. - [Solar Calculator](https://invoicemama.com/calculators/solar-calculator): Free solar panel calculator to calculate exactly how many solar panels you need, annual power generation, system costs, savings, and payback period for your home. - [Work Hours Calculator](https://invoicemama.com/calculators/work-hours-calculator): Calculate your daily and weekly work hours instantly. Handles breaks, overnight shifts, and converts to decimal hours for timesheets and payroll. - [EV Charging Calculator](https://invoicemama.com/calculators/ev-charging-calculator): Calculate how long it takes to charge your electric vehicle and estimate the cost based on your electricity rate. - [Markup Calculator](https://invoicemama.com/calculators/markup-calculator): Find selling price, markup percent, dollar markup, and gross margin. Switch modes to price from cost, back into markup from a list price, or work in dollars. - [Drywall Calculator](https://invoicemama.com/calculators/drywall-calculator): Calculate exactly how many drywall sheets you need - walls, ceilings, or both - with waste factor, openings, and optional cost estimate. - [Tile Calculator](https://invoicemama.com/calculators/tile-calculator): Estimate tile quantity, grout, thinset, and project cost from room dimensions, tile size, layout pattern, and optional pricing. - [Break-Even Calculator](https://invoicemama.com/calculators/break-even-calculator): Calculate how many units you need to sell - and how much revenue you need to generate - before your business starts making a profit. - [Concrete Calculator](https://invoicemama.com/calculators/concrete-calculator): Calculate cubic yards, cubic feet, bags needed, and estimated cost for any concrete shape - slabs, columns, stairs, rings, and more. - [Pipe Volume Calculator](https://invoicemama.com/calculators/pipe-volume-calculator): Calculate how much water any pipe holds. Enter inner diameter and length for gallons, liters, cubic feet, and system totals. - [Lawn Mowing Cost Calculator](https://invoicemama.com/calculators/lawn-mowing-cost-calculator): Price any lawn instantly. Contractor quote mode with margin checks, or homeowner market estimates by size and frequency. - [Snow Removal Pricing Calculator](https://invoicemama.com/calculators/snow-removal-pricing-calculator): Price driveways, commercial lots, and full plow routes by size, depth, and equipment. Per-visit, hourly, and seasonal estimates in seconds. - [Junk Removal Cost Calculator](https://invoicemama.com/calculators/junk-removal-cost-calculator): Calculate junk removal costs by load size, material type, crew, and pricing model. Multi-stop route totals built in. - [Square Footage Calculator](https://invoicemama.com/calculators/square-footage-calculator): Calculate area for any shape or room. Multi-room totals, unit conversion, waste factor, and cost estimate. Free, no signup. ## Frequently asked questions ### Are Invoice Mama calculators free to use? Yes. The calculators on this hub are free to use in your browser. You can run estimates for margins, materials, HVAC airflow, and other common contractor and small business scenarios without paying or creating an account. ### Do I need an account to use the calculators? No account is required for the public calculators. Open a calculator, enter your numbers, and read the results on the page. ### What kinds of calculators are in this collection? The hub includes business calculators such as profit margin, markup, break-even, and labor cost, plus trade-focused tools like HVAC CFM, roof pitch, decking, concrete, drywall, tile, solar, work hours, and EV charging estimates. ### How should I use calculator results on real jobs? Treat outputs as planning aids. Always double-check inputs, local codes, manufacturer specs, and site conditions. For bids and contracts, confirm numbers with your own measurements and professional judgment. ### Are calculator results saved on Invoice Mama? The public calculator pages are designed for quick checks in your session. Do not rely on the site to store your job data; save or export anything you need for your records. --- Invoice Mama is invoicing software for contractors, freelancers, and small businesses. It is not a tax, legal, or accounting firm. For current pricing, use the live pricing page. **More:** [Home](https://invoicemama.com/) - [Pricing](https://invoicemama.com/pricing) - [Guides](https://invoicemama.com/guides) - [Tools](https://invoicemama.com/tools)