Free Tools for Field Service Pros
Explore calculators that simplify pricing, payroll, ROI, and sizing for HVAC, plumbing, and beyond.
Manual J Load Calculator
Accurate heating and cooling loads using ACCA Manual J methodology - the national standard for HVAC sizing.
Manual S Equipment Selection
Check if HVAC equipment meets ACCA Manual S sizing limits. PASS/FAIL verdict for 8 equipment types.
Manual T Register Sizing
Size supply registers and return grilles room by room. Check face velocity and throw distance per ACCA Manual T.
Manual D Duct Design
Calculate friction rate, available static pressure, and duct sizes for every run. Flex and sheet metal supported.
Full HVAC System Design (J-S-T-D)
Run Manual J, S, T, and D in one workflow. Data flows between steps automatically - complete design in under 10 minutes.
BTU Calculator
Use a BTU calculator to size AC and heating systems the smart way.
AC Tonnage Calculator
Use the AC tonnage calculator to choose the right size unit, cut energy costs, and keep your space comfortable.
HVAC CFM Calculator
Find out how much airflow your HVAC system needs.
HVAC Duct Calculator
Calculate duct sizes, air flow, and pressure drops for HVAC systems.
Psychrometric Calculator
Get ASHRAE-accurate results fast with our free online psychrometric calculator for HVAC experts.
Profit Margin Calculator
Calculate your profit margins and markup percentages instantly.
Break-Even Calculator
Find out when your business will become profitable.
ROI Calculator
Calculate Return on Investment for your business decisions.
Get Paid Faster Calculator
See how much sooner you collect when you cut invoicing delays - and what faster payment is worth to your cash flow.
Sales Growth Calculator
Track and forecast your sales growth and revenue trends.
Salary to Hourly Calculator
Convert annual salary to hourly pay rate and calculate take-home pay.
Overtime Calculator
Calculate overtime pay and hours for your field service team.
Discount Calculator
Calculate discounts and final prices for your services.
Plumbing Business Valuation Calculator
Know what your plumbing business is worth in just a few clicks. Simple, fast, and useful for planning your next move.
Plumbing Labor Rate Calculator
Set the right price for your plumbing jobs. Enter a few details and get a clear labor rate you can trust.
Commercial Fire Sprinkler & Alarm System Cost Calculator
Quickly estimate the cost of a commercial fire sprinkler and alarm system. No guesswork - just a clean, easy number.
Run the numbers, then run the business
These calculators get you the number. Field Promax helps you act on it - scheduling, dispatch, work orders, estimates, and invoicing in one platform. Trusted by 100,000+ contractors across the USA and Canada.
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