🧪 Nutrient PPM Calculator
Get optimal nutrient concentration (PPM) and EC recommendations for every cannabis growth stage
Select Growth Stage
Choose the stage that best matches your plant's development
Recommended Nutrient Levels
Feeding Tips for This Stage
⚠️ Important Reminders
- Start at the lower end of the range and increase gradually
- Watch for signs of nutrient burn (leaf tip discoloration)
- Measure pH (5.5-6.5 for hydro, 6.0-7.0 for soil) after mixing nutrients
- Different strains may have different nutrient requirements
Understanding PPM and EC
What is PPM?
PPM (Parts Per Million) measures the concentration of dissolved nutrients in your feeding solution. It tells you how "strong" your nutrient mix is. Higher PPM means more nutrients, which plants need more of as they grow larger and enter flowering.
What is EC?
EC (Electrical Conductivity) measures how well your nutrient solution conducts electricity, which correlates to nutrient concentration. Measured in mS/cm (millisiemens per centimeter). Many professional growers prefer EC because it's more precise and doesn't vary between meter types like PPM does.
PPM Scales: 500 vs 700
Different meters use different conversion scales. This calculator uses the 500 scale (EC x 500 = PPM), which is most common in North America. If your meter uses the 700 scale (Truncheon), multiply the EC value by 700 instead. When in doubt, use EC values as they're universal.
Why Nutrient Strength Matters
Too low PPM leads to nutrient deficiencies (yellowing leaves, slow growth). Too high PPM causes nutrient burn (brown leaf tips, nutrient lockout). Following stage-appropriate PPM ranges ensures your plants get what they need without overfeeeding toxicity.
How to Use This Calculator
- Identify your plant's current growth stage based on age and development
- Select the appropriate stage from the dropdown menu
- Click "Get PPM Recommendation" to see optimal ranges
- Mix your nutrients according to manufacturer instructions
- Use a TDS/PPM meter or EC meter to measure your nutrient solution
- Adjust by adding water (to lower PPM) or more nutrients (to raise PPM)
- Always check pH after adjusting nutrients and before feeding
Frequently Asked Questions
How accurate is the nutrient PPM calculator?
This calculator provides industry-standard PPM ranges based on common cultivation practices. Individual plants may require adjustments based on genetics, growing medium, and environmental conditions. Start at the lower end of the range and increase gradually.
Is this tool free to use?
Yes! This tool is completely free with no hidden costs, subscriptions, or limitations. Use it as often as you need.
Do I need to create an account?
No account needed. The tool works entirely in your browser without requiring signup or personal information.
Does this work on mobile devices?
Yes, this tool is fully responsive and works on smartphones, tablets, and all desktop browsers.
Is my data private?
Absolutely. All processing happens locally in your browser. Your data never leaves your device and is not stored on any server.
What's the difference between PPM and EC?
PPM (parts per million) measures total dissolved solids in your nutrient solution. EC (electrical conductivity) measures how well the solution conducts electricity. They measure the same thing differently: EC x 500 = PPM (using the 500 scale). This calculator provides both values.