Jawad Hassan

About

I build free web tools that solve specific, everyday problems. Everything on calnconvert.com runs in your browser — no data leaves your device, no account required, no tracking.

I'm not a CPA or a tax attorney. I source formulas from official documentation — IRS publications, platform fee schedules, published API rates — and show the math openly so you can verify it yourself. If a tool produces an estimate rather than a definitive number, I say so explicitly.

How I build these tools

Every calculator here follows three rules I don't bend on:

• Source-linked math — formulas cite the official document they come from
• Client-side only — calculations run on your device, nothing is tracked or stored
• Honest estimates — variable outputs (like TikTok RPM) are clearly labeled with stated ranges, not presented as exact figures

Tools on this site

• Substack Revenue Calculator — net earnings after platform fee and Stripe costs
• TikTok Creator Rewards Estimator — earnings range based on published RPM data
• Freelancer Quarterly Tax Calculator — IRS 1040-ES based SE + income tax estimates
• Twitch Bits to USD Calculator — official $0.01/Bit creator payout rate
• BMI Calculator, Percentage Calculator, Loan Calculator, and more
• Unit converters for length, weight, temperature, area, volume, speed, and data storage

Other projects

• screenres.app— browser-based display diagnostics: pixel density, refresh rates, screen uniformity. I'm not a hardware engineer — I source from published specs and manufacturer data.
• dogfoodcostcalc.com— dog food cost estimator built on the same principles: veterinary-standard RER formula, 298+ breeds, transparent methodology.
• malkeeyat.com— real estate consultancy for residential and commercial properties in Lahore, Pakistan.