Parts Per Hour Calculator

Calculate injection molding production output from cycle time. This practical tool is an engineering estimate—validate decisions against machine, material, mold, and process data.

Formula and method

Hourly output = 3,600 ÷ cycle time × cavities × planned uptime.

Inputs and units

Enter measured or specified values in the displayed units. Keep units consistent; results are rounded for practical planning. This first release uses the displayed engineering units rather than a unit-switcher.

Worked example

3,600 ÷ 30 s × 4 cavities × 90% uptime = 432 parts/hour.

Start with a stable, defined cycle

Use a cycle that includes the actual mold, automation, and part-removal sequence. Enter cavities that are truly available for production, not the nominal cavity count if some are blocked or excluded.

Translate gross output into a plan

This output is a gross planning rate. Use Scrap Rate for quality loss and Machine Utilization for time loss before promising good-part output.

Sanity check a shift forecast

Hourly output multiplied by planned run hours should be compared with a recent production record. Large gaps usually point to cycle definition, availability, or quality assumptions.

Interpretation, assumptions, and limitations

This tool provides an estimate for planning and education. It does not replace machine maker limits, material data sheets, mold trials, cavity-pressure data, process validation, or qualified engineering review.

FAQ

Does planned uptime include scrap?

No. Uptime represents available running time. Apply a separate yield or scrap assumption when the target is good parts.