HVAC calculator

AC tonnage calculator

Compare an entered cooling-load scenario in kW, BTU/h and refrigeration tons. Includes an editable area factor.

By Feroz Sheikh · Formula GCC-COOLING-001 v1.0.0 · Tested formula

FormulaGCC-COOLING-001v1.0.0

Project inputs

Enter your measurements. Switching units converts the same project, including coverage and unit rates. Package yields keep the unit printed beside each field.

AC tonnage: measurement diagram. Measure the space and enter the stated planning factor. This sketch is not a room-by-room load design. — Measure the space and enter the stated planning factor. This sketch is not a room-by-room load design. View image

Room lengthft + inConditioned floor lengthftinRoom widthft + inConditioned floor widthftinScenario load per square metreW / m²150 is an illustrative scenario, not a recommended Qatar design factorAdditional scenario loadWEnter documented gains not already included in the area factor; avoid double counting

Refine measurements and rates at any time. Your current values are included in the material-list PDF.

Calculated result

1.066refrigeration tons

Cooling-load scenario

FormulaGCC-COOLING-001

kW = (floor area m² × entered W/m² + additional W) / 1000; tons = kW × 3412.141633 / 12000

3.75 kW

Cooling capacity

12795.5 BTU/h

Cooling capacity

25 m²

Conditioned floor area

Planning estimate, not engineering advice. Confirm site measurements and product specifications. Calculation limits.

Convert an explicitly entered cooling-load scenario into kW, BTU/h and refrigeration tons. The editable area factor lets you compare assumptions; it does not size equipment for a Qatar room.

Measure conditioned floor area.
Enter a documented area-load scenario or compare several assumptions.
Have a qualified HVAC designer calculate envelope, solar, occupancy, ventilation and latent loads before selecting equipment.

Add your project costs

Add rates if you are pricing a related project line. Pick a currency — badges, inputs, and totals follow.

This page is geometry, not a material takeoff. Leave rates at zero unless you are pricing a related line. Construclytic does not fetch supplier prices.

View estimate Quote / invoice Add another item

Embed this calculator

<iframe src="https://construclytic.com/embed/ac-tonnage" title="AC tonnage" width="100%" height="820" loading="lazy" referrerpolicy="strict-origin-when-cross-origin" style="border:1px solid #d7e0da;border-radius:16px;background:#fff;"></iframe>
<p><a href="https://construclytic.com/calculators/hvac/ac-tonnage" target="_blank" rel="nofollow noopener noreferrer">Calculator by Construclytic</a></p>

Paste on your website or blog. Includes a visible link back to this calculator.

How this calculator works

A transparent ac tonnage takeoff.

Feroz SheikhWritten by Feroz Sheikh · founderFormula GCC-COOLING-001 v1.0.0 automated checks Oct 3, 2026.

Convert an explicitly entered cooling-load scenario into kW, BTU/h and refrigeration tons. The editable area factor lets you compare assumptions; it does not size equipment for a Qatar room.

GCC-COOLING-001 is a transparent comparison of an entered area-load scenario, not a recommendation for buying an air conditioner. Showing kW, BTU/h and refrigeration tons together helps you discuss a documented design load with an HVAC contractor.

Worked example. A 5 × 5 m room with an illustrative 150 W/m² scenario and no extra gains gives 3.75 kW, about 12,795.5 BTU/h or 1.066 refrigeration tons. This is a scenario calculation, not a 1-ton purchase recommendation.

See the example inputs and calculated result

This separate example uses the calculator's starting values in imperial units. It stays unchanged when you edit the tool above. Example rates, yields and dimensions are assumptions, not recommendations for your project.

AC tonnage: example inputs
Input	Example value
Room length	16.404199 ft
Room width	16.404199 ft
Scenario load per square metre	150 W / m²
Additional scenario load	0 W

Example result: Cooling-load scenario — 1.066 refrigeration tons.

kW = (floor area m² × entered W/m² + additional W) / 1000; tons = kW × 3412.141633 / 12000

Use the labelled units above when reproducing this example. To work in metric, switch the calculator to Metric; applicable measurements are converted, while product-specific units remain labelled.

1. Measure conditioned floor area.
2. Enter a documented area-load scenario or compare several assumptions.
3. Have a qualified HVAC designer calculate envelope, solar, occupancy, ventilation and latent loads before selecting equipment.

Field notes that change the number

Ask the designer which outdoor dry-bulb and humidity conditions apply to the specific location.
Glazing direction, insulation and ventilation matter even for rooms with equal floor area.
Cooling capacity is thermal output; use manufacturer efficiency data for electrical consumption.

Common mistakes

Treating the illustrative 150 W/m² input as a Qatar design standard.
Choosing the next retail AC size from this simplified result.
Double counting internal gains already included in the entered area factor.

Need the broader workflow? Read the hvac planning guide.

Formula & assumptions

Show your work.

kW = (floor area m² × entered W/m² + additional W) / 1000; tons = kW × 3412.141633 / 12000

The area factor is an entered scenario, not a climate-based equipment recommendation.
No automatic solar, ceiling, glazing, humidity, ventilation or occupant correction is inferred.
A qualified designer must calculate local design loads and select equipment. This is not Manual J or an electrical power estimate.

Formula ID GCC-COOLING-001 · version 1.0.0. Automated regression checks passed 2026-10-03 · independent external engineering review is not claimed.

Tested 2026-10-03 by Feroz Sheikh.

Open this quote in 18 months and formula GCC-COOLING-001 still explains itself. Calculation method.

ACCA Manual J: detailed residential load calculation

ACCA Manual J residential load calculation

Questions

Questions about ac tonnage

Can floor area alone size AC for Doha?

No. Outdoor design conditions, glazing, insulation, infiltration, humidity and internal gains materially change the load. A detailed local design is needed.

How many BTU/h are in one ton?

One refrigeration ton is 12,000 BTU/h, approximately 3.517 kW of cooling capacity. Cooling capacity differs from electrical input power.

What is the formula ID?

This ac tonnage calculator publishes formula GCC-COOLING-001, version 1.0.0. The ID stays on the result and on the estimate line.