About CoinMetra

There is not much to explain about CoinMetra. It is a crypto profit and DCA calculator, and its job is calculating profit and loss after trading fees, the average cost of a dollar-cost-averaging plan, ROI and an estimated capital gains tax across nine countries. What follows is how it works, why it exists, and what it does with your data.

Why this site exists

Plenty of personal-finance pages already exist. Most of them make you dismiss a banner, ignore a modal and scroll past filler before the tool appears. CoinMetra inverts that: the tool is the page, it calculates profit and loss after trading fees, the average cost of a dollar-cost-averaging plan, ROI and an estimated capital gains tax across nine countries, and everything else is explanation you can read or skip.

How the maths is done

Everything runs on your own device. When you use the tool, it averages each buy by the amount invested rather than a simple price mean, deducts the fee from every trade, and applies the selected country's capital gains rules to the realised gain. Nothing about the method is hidden: if you want to check a result by hand, the description above is the algorithm the page actually uses, and every figure you see comes from it rather than from a black box.

Privacy by default

This is a local tool by construction. The buy and sell prices, amounts and fee percentages you enter never leave your device; there is no endpoint to receive them and no log to read them back from. Disconnecting from the internet after the page loads changes nothing about how it behaves.

Who it is for

• anyone doing the numbers before a decision.
• people modeling a plan over several years.
• readers who want the assumptions laid out.

Keeping the lights on

CoinMetra is free to use and supported by advertising. Adverts are kept off the working part of the page, and no advertiser receives anything you type. If a page ever becomes slow or intrusive, that is a bug worth reporting.

Contact

Spotted a mistake or missing a feature? The contact page takes it. The suggestions that get acted on usually come from people who actually use the crypto profit and DCA calculator.