Music and sound production

Compressor ratio output calculator

Static hard-knee transfer curve with ratio at least 1:1. Makeup gain is applied after compression. Attack, release, knee width and signal history are excluded.

Your numbers

Use the units shown. Results update as you change valid inputs.

YOUR RESULT

Static hard-knee transfer curve with ratio at least 1:1. Makeup gain is applied after compression. Attack, release, knee width and signal history are excluded.

THE NUMBERS, EXPLAINED

How to use this calculator.

Static hard-knee transfer curve with ratio at least 1:1. Makeup gain is applied after compression. Attack, release, knee width and signal history are excluded.

Start with your inputs

Enter input level (db), threshold (db), compression ratio, makeup gain (db). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.

InputExample value
Input level (dB)-6
Threshold (dB)-18
Compression ratio4
Makeup gain (dB)3

A worked example

With the example inputs above, output level (db) is -12. Change the inputs to explore your own scenario.

All results for the example inputs above
ResultExample answer
Output level (dB)-12
Gain reduction (dB)9

How this is calculated

Output level (dB)

At or below b, output = a+d. Above b, output = b+(a−b)/c+d.

Gain reduction (dB)

max(0, (a−b) × (1−1/c)). Makeup gain is excluded from the gain-reduction amount.

Symbols and units
a
Input level (dB)
b
Threshold (dB)
c
Compression ratio
d
Makeup gain (dB)

Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.

Assumptions and limits

Static hard-knee transfer curve with ratio at least 1:1. Makeup gain is applied after compression. Attack, release, knee width and signal history are excluded.

Calculations use the values you enter. Blank or invalid inputs show an error instead of silently substituting zero. Results are displayed to useful precision; calculations retain the underlying numeric precision.

Questions about this tool

What does the result tell me?

Output level (dB); Gain reduction (dB). The result applies to the method and inputs described above. Check the units and assumptions before using it in a decision.

Why might another calculator differ?

Differences in units, rounding, timing or model definitions can produce different answers. Compare the input definitions and the method, rather than only the final number. For this tool: Static hard-knee transfer curve with ratio at least 1:1. Makeup gain is applied after compression. Attack, release, knee width and signal history are excluded.

Are my inputs stored or sent to AI?

Calculations on this page happen in your browser. The separate AI question finder sends its submitted conversation to OpenAI; these calculator fields are not sent. Favourites and recent tool names are stored locally. A shared link contains the inputs you choose to include.

Further reading

OpenStax: algebra and proportional reasoning ↗

Background reading; this does not imply endorsement or independent review of SumFizz.

Review status

Software example and browser checks are recorded in our quality report. No external expert review is claimed. Created with coding assistance; calculations run as ordinary browser code.

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