Your bank gives you one exchange rate. Built into it is the bank's own mark-up, called the margin. This page takes the two apart.
Banks trade currencies with each other in the interbank market, the wholesale market where the real price is set. Your company cannot trade there directly, so you buy through a bank. The gap between that real price and the rate your bank gives you is the margin. Illustrative. Daily FX turnover: $9.6tn, BIS Triennial Survey, April 2025.
The real market price is built from many live sources, not from any single bank. It is a rate you could actually have traded at, not the "mid" (the midpoint between the buy and sell price), which nobody can deal on.
Companies: businesses with trades in our benchmark. Trades compared: individual customer trades checked against the real market price. Total value: the combined US dollar size of those trades. Saved for customers: documented savings across every customer, to date. As of mid-2026, across the Just benchmark network.
Here is exactly how we separate the real market rate from the bank's margin on a single trade.
For each trade, we take the confirmation your bank already sent you and compare its rate to the real market rate at that exact moment. The difference is the margin.
Every row is rebuilt from your own trade confirmation. Margin shown in PPM (parts per million): 1 basis point = 100 PPM. Names are fictional.
The FX Global Code is a voluntary standard signed by most major FX banks. It commits them to fair, reasonable mark-ups (Principle 14) and accurate, timestamped records (Principle 36). We never contact your bank; we only read the records you already hold.
For a company trading EUR 300 million of currency a year:
What you actually paid in margin last year, minus what you pay this year, measured on your real trades. No estimates.
Just is a yearly subscription, paid upfront. If the savings we can document in your first year do not exceed what you paid us, the guarantee covers the difference.
If they are, it's on us.
30 minutes, on your own trade data, no obligation.