Tools that just work

UA Tools started in 2026 with a simple frustration: most “free” online tools are slow, plastered with popups, or locked behind a sign-up wall. We build the opposite — small, fast, genuinely useful tools that open instantly and just work.

Every calculator on this site is built the same way: real math, transparent formulas, and results that update live as you type. No accounts, no email gates, no watermarks. If a tool cannot explain exactly how it got its answer, it does not ship.

What you will find here

Right now the collection focuses on calculators for real estate investors (BRRRR and house-hacking ROI, DSCR loans for Airbnb), equity compensation (RSU and stock option tax estimator), and cloud costs (AWS/Azure waste estimator). Each one exists because we needed it ourselves and could not find a version we trusted.

How the tools are made

• Real formulas, shown openly. Every tool documents its exact math on the page.
• Tested before publishing. Each calculator is verified against hand-computed examples.
• Fast by design. Single-file pages with no heavy frameworks, so they load instantly on any device.
• Honest limits. Estimates are labeled as estimates, with assumptions listed — never dressed up as professional advice.

What is next

We are adding new tools regularly — converters, more financial calculators, and everyday utilities. Have an idea for a tool, or spotted a bug in one? Tell us — reader requests genuinely shape what gets built next.