About OwlToolKit
OwlToolKit publishes free, fast calculators and tools that run in your browser, with no sign-up.
How we build and check our calculators
Every calculator is built from a written specification of the formula or rule it uses, and each page names its sources: official statistics, tax tables and rate notices such as BLS consumer price data, IRS and state revenue tables, and Reserve Bank of India or bank rate notices. We have 24 finance calculators so far.
Before a page goes live it has to pass automated tests: worked examples checked against the official figures, browser tests of the page itself, and site checks for broken links, titles and structured data. When an official source publishes new data, such as a new monthly CPI figure or a new tax year, we update the data and re-run the tests. Each finance page shows the date its content last changed.
Results are estimates for planning and education, not financial, tax or legal advice.
Corrections
If you find a mistake, email hello@owltoolkit.com with the page address and what you expected to see. We check the source and fix confirmed errors.
Advertising
The site is free and paid for by advertising (Google AdSense). Ads do not change any calculator result. See the privacy policy for cookies and your choices.
Questions
Who runs OwlToolKit?
OwlToolKit is an independent website that publishes free online calculators and tools. It is not affiliated with any bank, lender, government agency or financial adviser.
Is OwlToolKit financial advice?
No. Results are estimates for planning and education. Check important numbers with the official source linked on each page, or with a qualified professional.
Where does the data come from?
Each calculator cites its sources on the page, for example the Bureau of Labor Statistics for inflation, the IRS and state revenue departments for tax rules, and official bank or government rate notices.
Do you store what I type into the calculators?
No. The calculators run in your browser and the values you enter are not sent to our servers. Our privacy policy has the details.