Quantity is one division
Divide the capital by the buy price to get the fill quantity. The higher the price, the fewer coins the same money buys — an inverse relationship.
The buy fee is normally deducted from the fill, so the coins actually credited are multiplied by a further (1 − fee).
Formulas
capital ÷ pricecapital × (1 − fee) ÷ pricecredited quantity × current pricetarget quantity × price ÷ (1 − fee)Worked example (recompute it yourself)
Capital 3,000 USDT, buy price 25,000 USDT:
Without fees: quantity = 3,000 ÷ 25,000 = 0.12.
With a 0.1% buy fee: credited quantity = 3,000 × 0.999 ÷ 25,000 = 0.11988, which is 0.00012 less.
Valued at the buy price that difference is about 3,000 × 0.1% = 3.00 USDT — exactly the buy fee.
Quantity across price levels
| Buy price | Quantity, no fee (3,000 USDT) | Quantity with 0.1% fee |
|---|---|---|
| 3,000 USDT | 1.000000 | 0.999000 |
| 25,000 USDT | 0.120000 | 0.119880 |
| 60,000 USDT | 0.050000 | 0.049950 |
| 100,000 USDT | 0.030000 | 0.029970 |
Capital fixed at 3,000 USDT; quantity falls as the price rises.
Working backwards, and precision
To hold a target quantity, invert the formula: capital needed = target quantity × price ÷ (1 − fee). To hold 0.05 coins at 60,000 USDT with a 0.1% fee, you need 0.05 × 60,000 ÷ 0.999 ≈ 3,003.00 USDT.
When you actually place the order, the venue’s quantity precision and minimum order size apply, so the filled quantity may be rounded to the permitted number of decimals.
Notes
This converts at the price you enter. The real fill price is affected by slippage, especially on market orders.
Once you have the quantity, multiply it by the sell price and deduct the sell-side fee to get the net result of the trade.
Different coins use different decimal places and display precision, so keep enough significant digits when you reconcile.
FAQ
Why is the fee-inclusive quantity below "capital ÷ price"?
Because the buy fee is deducted from the fill — part of the money is taken before the conversion — so the credited quantity is scaled down by (1 − fee).
Is quantity × current price the position value?
Yes. Position value = credited quantity × current price, but it does not include the sell fee. What you actually receive after selling is charged again.
How do I work out the capital for a round number of coins?
Use target quantity × price ÷ (1 − fee). If the venue sets a minimum order size, the final filled quantity is rounded to that precision.