Fee discounts multiply. They do not add. That single fact is why a lot of people calculate their own trading cost incorrectly, and always in the same direction — they think they are paying less than they are.
This tool applies the layers in the order the exchange applies them, and shows you the difference against the addition method for comparison. It also lets you fold in the purchase premium, which is usually the largest cost of the lot and almost never appears in anyone's fee arithmetic.
How to use it, why there are no built-in rates, and how to read the output (expand)
Where each number comes from
Every field is something you look up rather than something we can supply. The base rate, the token discount and the referral reduction all sit on your own fee page once you are logged in. That page reflects your tier and your account, which no external source can know.
The premium field is the exception: it is the gap between the price you actually paid to acquire crypto and the mid-market rate at that moment. If you bought peer to peer, that gap is real money and it belongs in this calculation.
Why the tool contains no rate table
Because a stored rate would be wrong. Fee schedules move with tier, with promotions and with policy, and a number baked into a tool becomes misinformation on a schedule nobody controls. Worse, it becomes misinformation that people calculate with.
So the tool does arithmetic and nothing else. It cannot tell you your rate. That limitation is deliberate, and it is the same reason there is no fee table anywhere on this site.
Multiplying versus adding
A 25% discount followed by a 20% discount is not a 45% discount. It is 0.75 × 0.80 = 0.60, so 40%. The result shows both figures precisely so the gap is visible rather than theoretical, and the gap widens with every layer you add.
This matters most to people who have several discounts active and assume they are paying almost nothing. They are paying more than the addition suggests, every trade.
What the premium line does
If you enter a purchase premium alongside a trade size, the tool adds that layer and shows the combined cost as a percentage of the amount. When the premium exceeds the trading fee, it says so explicitly.
That warning appears more often than people expect. It is the single most useful output here, because it explains why optimising a fee tier can save nothing at all in practice.
What it does not include
Three costs are outside this calculation and have to be added separately: funding on perpetual positions, the bid-ask spread, and withdrawal fees. The funding rate converter handles the first. The other two depend on the pair you trade and the network you withdraw on — see withdrawal fees by network.
Nothing here leaves your browser
The calculator works entirely on your own device. What you type is only used to show you a result; it is not saved, not sent anywhere, and gone once you reload the page.
Read it as a comparison tool
The output is exactly as reliable as the numbers you put in. Use it to compare scenarios — with and without the token discount, at one tier versus another, with the premium included versus excluded — rather than as an authoritative statement about your account. For that, your own fee page is the answer.
The structure behind all of this, including the three costs that never appear under the word "fee", is in how fees stack.