Soil pH Adjustment Calculator – How Much Lime or Sulfur to Add to Your Soil

Correct your soil pH for optimal crop growth with our Soil pH Adjustment Calculator. Enter your current soil pH, target pH, soil type, and field area to calculate the exact amount of agricultural lime or sulfur to apply.

Current Soil pH

Test your soil with a pH meter or test kit

Target pH

Most crops prefer pH 6.0-7.0

Soil Type

Field/Garden Area

Adjustment Needed:

pH Adjustment Results

Enter values and click Calculate to see results

Understanding Soil pH

pH Difference = Target pH - Current pH

Lime Required = pH Diff × Soil Factor × Area / 100

pH Scale Reference

3.5-4.5: Very Acidic

4.5-5.5: Acidic

5.5-6.5: Slightly Acidic (Ideal for most crops)

6.5-7.5: Neutral

7.5-8.5: Alkaline

8.5+: Very Alkaline

Optimal pH for Common Crops

Potatoes: 5.0-6.0

Tomatoes: 6.0-6.8

Corn/Wheat: 6.0-7.0

Vegetables: 6.0-7.0

Alfalfa: 6.5-7.5

Other Free Tools

Search tools

Ph Calculator

pH Calculator – Calculate pH from H⁺ Concentration

Crop Yield Estimator

Crop Yield Estimator – Predict Your Farm's Harvest Before It Happens

Fertilizer Requirement Calculator

Fertilizer Requirement Calculator – Calculate NPK Fertilizer Dose Per Acre

Irrigation Water Calculator

Irrigation Water Calculator – Calculate Water Needed for Crop Irrigation

Pesticide Dilution Calculator

Pesticide Dilution Calculator – Calculate the Right Pesticide-to-Water Ratio

Seed Rate Calculator

Seed Rate Calculator – Calculate Seeds Per Acre for Optimal Crop Yield