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Calcimator

Garbage Disposal Sizing Calculator

Find the right garbage disposal horsepower for your household based on family size, cooking habits, and food waste types.

Inputs

Results

Recommended HP

0.75

Usage intensity score4
Chamber size (cu. in.)34
Typical motor RPM2,800
Estimated amps (120V)6
Price range low ($)$120.00
Price range high ($)$250.00
Permanent magnet motor?1
Batch feed recommended?0
Septic-compatible needed?0
Hp Label3/4 HP
How to Use This Calculator
  1. Enter the number of people in your household — larger families need higher HP motors.
  2. Set your cooking frequency: 0 = rarely, 1 = a few times per week, 2 = daily, 3 = multiple times daily.
  3. Toggle Hard Foods to 1 if you grind bones, fruit pits, or shellfish shells regularly.
  4. Toggle Septic System to 1 if your home uses a septic system — this raises the HP recommendation.
  5. Review the Recommended HP, Estimated Amps, and Price Range to find the right disposal model.

What each input means

Household size (people)
Number of people in the household.
Cooking frequency (0-3)
0 = rarely, 1 = few times/week, 2 = daily, 3 = multiple times/day.
Hard foods? (0=No, 1=Yes)
Will you grind bones, fruit pits, or shellfish shells?
Septic system? (0=No, 1=Yes)
Septic systems need higher-end disposals with finer grinding.

What each result means

Recommended HP
Motor horsepower rating to look for.
Usage intensity score
Internal score (1-10) driving the HP recommendation.
Chamber size (cu. in.)
Approximate grinding chamber volume in cubic inches.
Typical motor RPM
Expected motor speed. Permanent magnet motors spin faster.
Estimated amps (120V)
Current draw on a standard 120V, 15A kitchen circuit.
Price range low ($)
Budget end of the recommended HP tier.
Price range high ($)
Premium end of the recommended HP tier.
Permanent magnet motor?
1 = recommended (quieter, lighter); 0 = induction is fine.
Batch feed recommended?
1 = safer batch-feed type recommended; 0 = continuous feed OK.
Septic-compatible needed?
1 = choose a septic-assist model with enzyme injection.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Household size (people) = 3, Cooking frequency (0-3) = 2, Hard foods? (0=No, 1=Yes) = 0, Septic system? (0=No, 1=Yes) = 0 = 4 input(s) provided
  2. Calculate Recommended HP
    0.75 = 0.75
  3. Calculate Usage intensity score
    4 = 4
  4. Calculate Chamber size
    34 = 34

Engine last updated . Checked against 2 independently-derived tests — how we verify calculators.

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