CO2 Grow Room Calculator
Room enrichment, ventilation losses & cylinder budgeting.
Editable room examples — target concentration is crop-specific.
Room & Equipment Inputs
Enrichment & Supply Summary
Example calculation1.50 cu ft · 400 → 1,250 ppm
Room & CO₂ Flow Visualizer
Illustrative layout, not to scale; target label is not a sensor reading.One loss-adjusted boost + 12 h target hold; no reserve or extra losses.
Use calibrated CO₂ sensing and local exposure requirements. Burner systems also need CO monitoring and qualified installation.
Model Checks
- 1Measure dimensions & existing CO₂
- 2Include ventilation and measured uptake
- 3Verify delivered flow with monitoring
Gas demand is an estimate, not an automatic equipment setting.
Formula & Worked Example
Frequently Asked Questions
Why does ventilation change injection time?
Air exchange removes added CO₂ toward the entered ambient concentration. The dilute-gas model assumes a well-mixed room, constant flow, constant ACH and constant entered uptake. It neglects the small displacement caused by the injected gas. The sealed boost number and the actual gas delivered during the loss-adjusted boost are different.
What if flow cannot reach the target?
When delivered CO₂ flow is no greater than ventilation demand plus entered uptake at the target, a finite boost cannot attain that target in this model. At exactly balanced flow the target is approached asymptotically. The tool shows an unreachable result instead of an infinite or fabricated injection time.
Does tank life include plant uptake?
Only the uptake value you enter. Zero omits uptake rather than proving there is none. Daily budget includes the selected number of loss-adjusted boosts plus target-hold hours times maintenance demand. Nominal tank mass has no reserve, regulator loss or extra leakage allowance; actual cylinder life may differ.
Is 2,000 ppm a universal safety limit?
No. A target at or above 2,000 ppm triggers a high-enrichment planning notice, not a human exposure diagnosis. NIOSH and OSHA publish time-weighted occupational references, including 5,000 ppm TWA; NIOSH also lists 30,000 ppm short-term and 40,000 ppm IDLH. Below these values is not a safety clearance. This calculator does not measure exposure or oxygen and does not replace monitoring or local requirements.
More calculation questions
What does this CO₂ Grow Room calculator calculate?
Room volume, approximate sealed initial enrichment gas, a constant-flow loss-adjusted boost time, maintenance CO₂ flow, and a nominal daily gas budget/cylinder duration. It is not a carbon footprint or fuel-consumption calculator.
Which values should I enter?
Use measured inside dimensions and the current/ambient concentration, your crop-specific target, actual delivered pure-CO₂ or manufacturer-rated CO₂ output, air changes and any measured or estimated uptake. The entered ambient value is also the assumed starting concentration and incoming ventilation concentration.
What formula is used?
Sealed boost L = room m³ × max(target − ambient ppm, 0) / 1,000. Maintenance L/h = ACH × sealed boost L + uptake L/h. The model solves the first-order well-mixed trace-gas balance for boost time. Daily L = boosts × actual boost gas + hold hours × maintenance.
Are the gas-volume units standard conditions?
The displayed gas volumes, L/min and CFH conversions are all assumed at 20°C and 101.325 kPa. CFH means cubic feet per hour; 1 ft³ = 28.316846592 L. A meter rated at different reference conditions needs its manufacturer’s correction. Nominal cylinder gaseous volume uses an ideal-gas conversion, not the cylinder’s liquid or internal volume.
Why might another source give different results?
Sealed estimates omit air exchange and uptake. Other models may assume another temperature, pressure, supply purity, start concentration, schedule, reserve or mixing pattern. A fixed plant-uptake term and constant ACH cannot capture every greenhouse condition.
Does the result update immediately?
Yes. Dimensions, units, concentration, delivered flow, source and daily budget inputs update immediately. Invalid values clear results and disable copying. Switching m/ft, L/min/CFH and lb/kg preserves the same physical quantity.
Can I use this as an automatic equipment protocol?
No. It is a planning estimate, not a control schedule or installation approval. Use calibrated sensing, appropriate ventilation and professionally selected equipment. Generator mode requires manufacturer-rated CO₂ output; it does not model raw exhaust, fuel use, carbon monoxide, heat, oxygen consumption or other combustion products.
Does a lower target remove CO₂?
No. If the target is below the entered ambient/start level, adding gas cannot lower it. The tool does not produce an injection plan for lowering concentration. Crop response also depends on light, temperature, nutrition, moisture and species; no target is a universal yield recommendation.
Sources & References
Oklahoma State ExtensionGreenhouse CO₂ supplementation
CDC / NIOSHCO₂ exposure reference & monitoring contextReference information is not institutional endorsement.
Estimate room enrichment CO2, loss-adjusted injection time, maintenance demand and nominal cylinder budget from dimensions and delivered flow.