How I built a fast SaaS Pricing Calculator in Vanilla JS

As developers building micro-SaaS projects, we often need a quick way to model our pricing tiers and project potential revenue. I was tired of using complex spreadsheets, so I built a clean, client-side SaaS Pricing Calculator.

The Approach

I wanted to keep it 100% Vanilla JS for maximum performance and security. No server calls, complete data privacy for your business metrics.

Here is a quick look at how the core logic handles the MRR (Monthly Recurring Revenue) calculation:

function calculateSaaSRevenue(users, monthlyPrice, churnRate) {
    const grossMRR = users * monthlyPrice;
    const churnedRevenue = grossMRR * (churnRate / 100);
    const netMRR = grossMRR - churnedRevenue;

    return {
        grossMRR: grossMRR,
        netMRR: netMRR,
        annualRevenue: netMRR * 12
    };
}

Try it out

You can use the live tool for free here: SaaS Pricing Calculator

Let me know what you think or if you'd add any other metric calculations in the comments!