Principal — Principal amount borrowed. Larger amount increases periodic payments and total interest; compare to down payment. Example: 0.1.

Principal is required

Rate — Rate as a percentage. Determines how quickly interest or growth accrues; even 0.5% changes matter over time. Example: 0.1.

Rate is required

Time — Time spent. Track actual minutes to improve the hourly rate estimate. Example: 0.1.

Time is required