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    HVAC calculators that work from the truck

    Sizing, airflow, refrigerant and pricing math with the formulas shown, built for a phone with one thumb free. Every result has a share link so you can send it to the office or the customer.

    Equipment sizing

    Airflow & ductwork

    Refrigerant charging

    Job cost estimators

    Pricing & profit

    The calculators are free. The estimates are the business.

    EstimateKit builds good-better-best estimates customers approve from their phone, then runs the job, the invoice and the follow-ups. $49/month, 14-day free trial.

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    How these calculators are built

    Every tool shows its formula and its assumptions on the page, so you can check the math against your own numbers or a manufacturer chart. The sizing tools are rule-of-thumb block loads for quick checks and sales conversations, not a replacement for a Manual J. The refrigerant tool uses published pressure-temperature data at 10°F steps with linear interpolation between them. The cost estimators use 2026 national installed-price ranges and say so.

    Inputs are saved in the page address as you type. Copy the link from your browser and the person you send it to sees the same numbers.

    Complete business software for HVAC contractors. Estimates, customers, jobs, and invoicing — all in one platform.

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