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Composting Recovery Rate Estimator

The Composting Recovery Rate Estimator measures the share of incoming feedstock retained as finished compost after processing losses. It compares recovered output with the total material entering the defined reporting period and expresses the ratio as a percentage. For a composting operation, this metric can be used to track process yield, contamination and residue impacts, or changes in material quality over time. The numerator and denominator should refer to the same batch, facility boundary, and time period; otherwise the rate can be distorted by inventory carried between periods. The calculator also shows unrecovered tons and the complementary unrecovered share. A recovery rate is a mass-balance indicator rather than a measure of product quality, environmental benefit, or economic value, so those outcomes should be evaluated separately.

Material recovery inputs

tons
tons
Result
—
material recovery rate
Recovered material—
Unrecovered material—
Unrecovered share—

1. Enter total input material
Use the tons of organic feedstock entering the chosen process boundary during the reporting period.

2. Enter recovered output
Provide the tons counted as finished compost from that same input population and period.

3. Keep boundaries consistent
Do not mix one month of input with output that includes inventory from another month unless you make an inventory adjustment outside the calculator.

4. Review recovery rate
The main percentage is recovered tons divided by input tons. The breakdown shows tons and percentage not recovered.

Recovery rate (%) = Recovered output tons / Input tons × 100 Unrecovered tons = Input tons − Recovered output tons Unrecovered share (%) = 100 − Recovery rate

Both mass inputs must use the same unit. This page uses tons, but the ratio would be the same with another consistent mass unit. Recovered output cannot exceed total input in this simple mass-balance model.

What the result means

The percentage is the share of input mass that is counted as recovered output within the defined process and reporting boundary.

Mass loss does not automatically equal disposal. Moisture loss, biological conversion, evaporation, sampling differences, and inventory changes may need separate treatment depending on the process and reporting objective.

Given: 1,000 tons of input material and 430 tons of recovered output.

Calculation:
Recovery rate = 430 / 1,000 × 100 = 43.0%.
Unrecovered material = 1,000 − 430 = 570 tons.
Unrecovered share = 100% − 43.0% = 57.0%.

Result: The recovery rate is 43.0%.

Interpretation: About 43.0% of the incoming mass is counted as recovered output under this reporting boundary, while 57.0% is not.

Should the input and recovered tons cover the same dates?

Yes. Use matching process and reporting boundaries whenever possible. If material remains in inventory across periods, adjust the mass balance before interpreting the rate as process performance.

What if recovered output is greater than input?

That usually indicates mismatched periods, measurement differences, added material, or inventory carryover. This simple calculator flags recovered tons above input because it assumes a closed input-to-output mass comparison.

Is unrecovered material always waste?

No. Depending on the process, the difference can include moisture loss, biological conversion, screening loss, contamination, disposal residue, or measurement error. Interpret it using process-specific records.

Can I compare recovery rates between facilities?

Only when both facilities use comparable definitions for input, recovered output, contamination, moisture, and reporting periods. Different accounting boundaries can create misleading comparisons.

How is recovery rate different from diversion rate?

Recovery rate focuses on material output relative to process input. A diversion rate often compares material kept out of disposal with a broader generated-waste total, so its denominator and scope can differ.