About PennyCompass

What we do

PennyCompass publishes free finance calculators for the United States. We cover taxes, paycheck and take-home pay, retirement, mortgages, equity compensation, crypto tax, freelance and business finance, personal finance, and insurance.

Every calculator on this site is built around official primary sources (IRS, SSA, state revenue departments). We show our work: every page lists the sources it is built from and its last verification date.

Why this site exists

Most finance calculators on the open web fall into two buckets. The first is the giant finance portal (Bankrate, NerdWallet, SmartAsset), these are excellent at scale but sometimes simplify too much to be useful for specific situations. The second is the lead-gen tool from a tax firm or brokerage, these are accurate but built to funnel customers into a product, not to answer your question.

We are building a third option: deep, jurisdiction-aware, ad-supported tools that don’t require login, don’t up-sell you, and are precise enough to actually plan with. Our goal is to be the single best free finance toolkit for the US, then the UK, then Canada, Australia, and beyond.

Who we are

The PennyCompass team builds and maintains the calculators and guides on this site. Every tool is researched against official primary sources, the tax authority, social-security or pension agency, and central bank for the country it covers, and each page lists the sources it draws on and the date it was last checked. We publish the underlying math openly so it can be inspected and corrected.

You can reach us via the contact page.

Editorial process

1. Every calculator is researched against the relevant primary source for its country (for example an IRS publication, HMRC guidance, a state or provincial revenue schedule, or a central-bank notice).
2. The math is implemented in clean, type-safe TypeScript, and each page's worked example is checked against the tool's own output.
3. Each page lists the specific sources it is built from and the date it was last checked, so you can verify the figures yourself.
4. Figures are re-checked every tax year, or whenever the underlying law changes. The "Last updated" date on every page reflects the most recent check.
5. These tools are educational and not personal financial advice. We are engaging credentialed reviewers per jurisdiction and will name them here as they come on board.

See the full methodology for details.

How we’re funded

This site is supported by display ads and affiliate links. We may earn a commission if you click an affiliate link and complete a purchase. Affiliate relationships never affect how we compute or present calculator results.

See disclaimer and privacy policy for the full details.