Craft your app with robust payroll calculations

The commercial PaymentEvolution Payroll web services API is available for integration with your custom application or service. From simple payroll deduction calculations to complex benefits and custom earnings - we work with you to implement the set of services you need.

Common API requests

  • Simple deduction calculations based on current tax tables - use a standard set of input variables to receive the calculated result
  • Custom deductions, benefits and earnings - extend our API to include any number of custom calculations for your service
  • History - extend the API to store historical calculations, employee profiles etc


For simple calculations you can embed our skinnable widget in your site. Contact us for details and licensing terms.

Getting started

You'll need an authorized API account which you can register for by contacting us. Calculations are performed using pre-paid bundles:

  • 1,000 calculations/month for $500
  • 100,000 calculations/year for $30,000

If you need a larger bundle, please get in touch. At this time, we do not offer smaller packages.


Bundles are payable online or through terms established with us

Bundles expire after one year, when the bundle term expires, or when the number of calculations have run out.

Unused calculations may not be carried forward

Each call made to the API counts as one calculation, regardless of the number of results returned by the call

You may check the number of calculations remaining in your bundle via the API

Real payroll, payslips, T4s and more - free, sign up:

No risk 15-day trial. No credit cards required. Free plans available