A Predetermined Overhead Rate is Calculated by Dividing

Predetermined Overhead Rate Calculator

Understanding Predetermined Overhead Rates

In cost accounting and manufacturing, a predetermined overhead rate is a crucial tool used to allocate indirect manufacturing costs (overhead) to products or services. This rate is calculated before a period begins (e.g., a fiscal year or quarter) and is used throughout that period to apply overhead costs to production. This approach helps in more accurate product costing, pricing decisions, and performance evaluation.

How is a Predetermined Overhead Rate Calculated?

The fundamental formula for calculating a predetermined overhead rate is straightforward:

Predetermined Overhead Rate = Total Estimated Overhead Costs / Total Estimated Allocation Base

The Total Estimated Overhead Costs represent the sum of all anticipated indirect costs for the period. These costs can include items such as factory rent, utilities, depreciation of equipment, indirect labor (supervisors, maintenance staff), factory supplies, and insurance.

The Total Estimated Allocation Base is the measure that is believed to have the most direct relationship with the incurrence of overhead costs. Common allocation bases include:

• Direct Labor Hours: Assumes overhead costs are driven by the amount of time workers spend directly on production.
• Direct Labor Costs: Similar to direct labor hours, but uses the cost of direct labor as the base.
• Machine Hours: Used when a significant portion of overhead is related to machine usage and operation.
• Units Produced: A simpler method, often used in mass production environments.

For the purpose of this calculator, we are using Direct Labor Hours as the allocation base, as it is a very common and often reliable method.

Why Use a Predetermined Overhead Rate?

• Timeliness: It allows for the application of overhead costs to production as it occurs, rather than waiting until the end of the accounting period when actual costs are known. This provides more current information for decision-making.
• Stability: It smooths out fluctuations in overhead costs and activity levels. Actual overhead costs can vary significantly due to seasonality or production surges, which could distort product costs if actual rates were used.
• Cost Control: By comparing applied overhead to actual overhead, management can identify variances and investigate potential inefficiencies or overspending.

Example Calculation

Let's consider a manufacturing company that is estimating its overhead for the upcoming year. The company anticipates the following:

• Total Estimated Overhead Costs: $500,000 (This includes rent, utilities, salaries for supervisors, indirect materials, etc.)
• Total Estimated Direct Labor Hours: 25,000 hours (This is the total number of hours the direct workforce is expected to spend on production.)

Using the calculator formula:

Predetermined Overhead Rate = $500,000 / 25,000 hours = $20 per direct labor hour.

This means that for every direct labor hour worked on a product, the company will apply $20 of overhead cost to that product. If a product requires 3 direct labor hours to manufacture, $60 ($20 x 3) in overhead will be allocated to it.