How do you calculate an injection molding machine hour rate?

Divide total annual machine costs by available production hours, then multiply by an overhead allocation factor. With $180,000 in annual costs over 6,000 hours and a 1.25x overhead multiplier, the base rate is $30/hr before overhead and $37.50/hr fully burdened.

What costs belong in the annual machine cost figure?

Depreciation or lease, energy and chilled water, hydraulic and screw maintenance, planned downtime for PM, machine insurance, and an allocation of building rent and indirect labor tied to that press.

What is a good machine hour rate for injection molding?

It depends entirely on tonnage. Small all-electric presses under 100 tons often run $25-45/hr, mid-range 200-400 ton presses $40-75/hr, and large 1,000 ton+ machines $90/hr and up. Benchmark within a tonnage class, not across the whole shop.

Why use available hours instead of calendar hours?

Calendar hours assume 24/7/365 perfection. Available hours subtract holidays, planned maintenance, and realistic non-running time, which spreads fixed cost over hours you can actually sell and avoids systematically under-pricing.

Machine hour rate vs cycle-based costing - what is the difference?

The machine hour rate is the dollars per hour input. Cycle-based costing multiplies that rate by cycle time per shot and divides by cavities to get conversion cost per part. You need the hour rate first.

How does the overhead multiplier change the rate?

The multiplier loads indirect costs not captured in the direct machine line, such as supervision and quality overhead. A 1.25x multiplier raises a $30 base rate to $37.50, a 25% uplift applied to every quoted hour.

Injection Molding calculator

Injection Machine Hour Rate Calculator

The machine hour rate is the fully burdened cost of running an injection molding press for one hour, and it sits at the heart of every plastic part quote. Estimators, cost engineers, and plant controllers use it to convert cycle time into conversion cost so quotes reflect real depreciation, energy, maintenance, and floor overhead rather than guesswork. Get this rate wrong and every part that runs on that tonnage class is mispriced. Larger-tonnage presses carry higher hourly rates because of higher capital cost, clamp energy, and floor space, so most shops maintain a separate rate per tonnage band.

What this calculator does

Calculate the fully loaded hourly rate for an injection molding press including depreciation, utilities, maintenance, and overhead.
Use this when building part cost quotes, comparing press economics across machine sizes, or allocating machine costs to different product lines.
It divides total annual machine costs by available production hours and applies an overhead multiplier to give a fully burdened press cost per hour.

Formula used

Machine hour rate = (Annual costs / Available hours) x Overhead multiplier
Use this rate in part cost calculations along with cycle time

Inputs explained

Total annual machine costs:
Available production hours per year:
Overhead allocation multiplier:

How to use the result

Use it when building a part cost model or quote, or when re-baselining shop rates at the start of a fiscal year or after a capital purchase.
It assumes the press runs at the budgeted utilization; if actual uptime falls well below available hours, the true cost per running hour is higher than the figure shown.

Current U.S. benchmarks

The producer price index for plastic resins and materials stands at 319.371 (BLS, May 2026), up 19.5% from a year earlier. Quotes priced off last quarter's material cost miss this move.
The U.S. has 9,635 plastics product manufacturing establishments employing about 677,302 workers (Census County Business Patterns, 2023).

Common questions

How do you calculate an injection molding machine hour rate? Divide total annual machine costs by available production hours, then multiply by an overhead allocation factor. With $180,000 in annual costs over 6,000 hours and a 1.25x overhead multiplier, the base rate is $30/hr before overhead and $37.50/hr fully burdened.
What costs belong in the annual machine cost figure? Depreciation or lease, energy and chilled water, hydraulic and screw maintenance, planned downtime for PM, machine insurance, and an allocation of building rent and indirect labor tied to that press.
What is a good machine hour rate for injection molding? It depends entirely on tonnage. Small all-electric presses under 100 tons often run $25-45/hr, mid-range 200-400 ton presses $40-75/hr, and large 1,000 ton+ machines $90/hr and up. Benchmark within a tonnage class, not across the whole shop.
Why use available hours instead of calendar hours? Calendar hours assume 24/7/365 perfection. Available hours subtract holidays, planned maintenance, and realistic non-running time, which spreads fixed cost over hours you can actually sell and avoids systematically under-pricing.
Machine hour rate vs cycle-based costing - what is the difference? The machine hour rate is the dollars per hour input. Cycle-based costing multiplies that rate by cycle time per shot and divides by cavities to get conversion cost per part. You need the hour rate first.

Last reviewed 2026-05-12.