FixMyFX

FixMyFX is a free, no-sign-up calculator built for founders who sell or spend in foreign currencies. Its purpose is straightforward: show you what FX fees are costing your business and what you could do about it. You enter your annual revenue, the share of it in foreign currency, your annual expenses, and the share paid in a foreign currency. The tool then estimates roughly what FX fees cost you per year and gives you a plain-English plan to minimise those costs by receiving and spending in the same currency — for example, using a multi-currency account from Wise or Airwallex alongside a local bank. The calculation runs entirely in your browser: none of your numbers are collected, sent to a server, or tracked. The problem FixMyFX addresses is stated directly on the site: most founders get charged FX fees twice, on income and on expenses. The share text used by the tool puts it plainly — most founders lose 2–5% of revenue to hidden FX fees. On the income side, Stripe auto-conversion is described as charging 1% (US) or 2% (UK/EU/Rest) on inbound foreign revenue. On the spending side, a bank FX markup of around 3% is described as a typical bank spread on foreign spending and subscriptions. The calculator labels this combined situation the "lazy tax" — the cost of a standard single-currency setup in which you use your local bank for everything. These costs are easy to miss individually but compound over a 12-month period, quietly taking money that could otherwise stay in the business. The tool is also explicit about who does not need it: if your company, clients, and suppliers are all in the same country, you probably don't need it. FixMyFX starts by asking where your company is registered, offering the United Kingdom (GBP), United States (USD), Eurozone (EUR), Australia (AUD), Canada (CAD), the Nordics (DKK/NOK/SEK), New Zealand (NZD), Singapore (SGD), and Other (USD). That choice sets the home currency for the calculation. It then asks how you manage currency, with two options: Single Currency, described as using your local bank for everything (the standard setup), and Multi Currency, described as holding funds in multi-currency accounts (an FX-optimised setup). From there you enter your annual revenue per year together with the percentage in foreign currency, and your annual expenses per year together with the percentage paid in foreign currency — with SaaS tools, ads, and hosting paid in USD given as examples. You then execute the calculation, or update it when you change an input. The results screen places two setups side by side. Under "Current setup (lazy tax)", the tool models Stripe auto-convert plus bank FX and shows estimated annual fees. Its own explanation of the calculation is twofold: Stripe auto-conversion of 1% (US) or 2% (UK/EU/Rest) on inbound foreign revenue, and a bank FX markup of roughly 3% as a typical bank spread on foreign spending and subscriptions. Under "FixMyFX setup (zero leak)", it models a multi-currency account and shows estimated annual fees. That calculation is explained in three parts: direct payout at a 0% fee, meaning you receive foreign currencies into matching multi-currency bank accounts; direct spend at a 0% fee, meaning you pay foreign bills directly from matching currency balances; and a net profit transfer at roughly 0.4% fee, meaning interbank rate conversion only when moving balances home. The gap between the two estimates becomes the potential annual savings, calculated over a 12-month period. When there are savings to capture, FixMyFX explains how to achieve them in four numbered steps. First, open a multi-currency account (e.g. Wise Business, Airwallex) matching the currencies your customers pay in (EUR/GBP/USD). Second, connect these local bank accounts to Stripe so payouts land directly without Stripe's 1–2% auto-conversion markup. Third, pay foreign expenses such as SaaS, ads, and overseas contractors directly from those currency balances with zero FX spread. Fourth, convert only what is left back to your home currency at transparent ~0.4% interbank rates. The tool also translates the estimated saving into equivalencies, listing MacBooks Pro, months of Claude Max 20x, months of Claude Max 5x, months of Claude Pro, and fancy coffees. You can share the result on Twitter/X or LinkedIn, optionally including your savings amount. If your inputs already describe an optimised setup, the tool switches to a "You are winning!" state instead. That state states you are already using an optimised setup, that most founders lose money per year on this volume but you keep it, that this is because you don't auto-convert revenue (saving 1–2%), and that paying expenses directly from your foreign currency balances stops the FX leak completely; the annual fees shown in that case assume you pay a ~0.4% conversion fee only on the net profit you bring home. The distinctive methodology behind FixMyFX is that typically FX tools compare transfer rates, whereas this tool looks at your whole flow — income and spending. Rather than optimising a single transfer, it models the money coming in and the money going out, then compares a standard single-currency setup against a multi-currency, FX-optimised setup. The entire calculation runs in your browser, and the site states that none of your numbers are collected, sent to a server, or tracked. That means you can get an estimate without creating an account, without a sign-up, and without any of your figures leaving your device — a design choice that also makes it practical to test several scenarios quickly and privately. For users, the outcome is visibility plus a concrete path to saving. Instead of guessing whether FX fees matter at their volume, a founder sees an estimated annual fee figure for their current setup, an estimated annual fee figure for an FX-optimised setup, and the difference, described as money going back into the business every year. The four-step plan turns that estimate into action by naming the specific moves: opening a multi-currency account, connecting it to Stripe for direct payouts, paying foreign expenses from matching currency balances, and converting only the remainder at transparent interbank rates. The equivalencies — MacBooks Pro or months of Claude subscriptions — reframe an abstract percentage as things the business could otherwise buy, and the built-in sharing options let a founder circulate the result, optionally with the savings amount included. Concrete scenarios where FixMyFX fits are the ones its inputs describe. A founder whose customers pay in EUR, GBP, or USD while the company is registered elsewhere can enter annual revenue and the share received in foreign currency to see what Stripe auto-conversion costs them. A business paying SaaS tools, ads, and hosting in USD can enter those expenses and the percentage paid in foreign currency to see what a typical bank FX spread adds on top. Someone deciding whether to move from a single-currency setup to a multi-currency one can switch the currency-management choice between Single Currency and Multi Currency and compare the two fee estimates. A founder who already holds funds in multi-currency accounts can run their numbers to confirm they are in the "You are winning!" state. And anyone who wants to know the size of the prize before doing the work can use the savings figure and the equivalencies to justify the change. The product is aimed squarely at founders who sell or spend in foreign currencies, and the site notes that if your company, clients, and suppliers are all in the same country, you probably don't need it. It is free — no sign-up, no account required — and it runs in the browser on the web. Named in the content are the accounts and services it references: Wise Business and Airwallex multi-currency accounts, Stripe and its payout and auto-conversion behaviour, and local banks. It also lets you support the builder with a voluntary, non-refundable gratuity in USD, GBP, or EUR at $5, $15, $25, or a custom amount. FixMyFX was built by Tania Bell, described as a product manager who can code and an ex-finance manager, and it carries a disclaimer that it provides estimates based on standard publicly available fee structures, does not constitute financial advice, and that you should always check your own bank's PDS. In short, FixMyFX is a free, browser-only calculator that shows founders what FX fees are costing them across their whole flow, compares their current setup against a multi-currency one, and then hands them a plain-English four-step plan for keeping more of their revenue in the business.