kappi.me

ask AIs about kappi

Trading Fee Calculator

Fees look small per trade and enormous per year. Enter your position size, commission, spread and trade frequency, and this returns the cost per round trip, the annual total, and the percentage of your account it consumes.

Calculator by kappi.me

The number that changes behaviour

Per trade, the default costs $7.50 — genuinely trivial against a $5,000 position. Twenty times a month, twelve months a year, it is $1,800: 7.2% of a $25,000 account, paid every year regardless of whether the trading worked.

That is the figure to hold in mind. A strategy must clear 7.2% annually before it has made a cent, and most published equity market returns are not much above that. Frequency, not fee rate, is what makes trading expensive.

Slippage is usually the bigger half

Commissions are visible on the statement and easy to obsess over. Slippage — the gap between the price you intended and the price you got — is invisible unless you deliberately measure it, and on anything less than a deeply liquid instrument it typically exceeds the commission.

To measure it: record your intended price when you send the order, compare against the fill, and average the difference over fifty trades. Most traders who do this for the first time find their real cost is roughly double what they assumed. Put that measured number in the spread field rather than the broker's quoted spread.

What actually reduces the bill

  • Trade less. Cutting from 20 round trips a month to 10 halves the annual cost outright. No other change comes close.
  • Use limit orders. They convert a taker fee into a maker fee on exchanges that distinguish, and they cap slippage by construction.
  • Trade liquid instruments. The spread on a thin small-cap or an obscure altcoin can be several percent per round trip.
  • Negotiate the rate. Meaningful at high volume, irrelevant at low. Check where you actually are before spending time on it.

Fees and edge are the same subtraction

An honest expectancy figure is net of costs. Run your numbers through the expectancy calculator using net results, not gross — a system with a small positive gross edge and a normal fee bill is very often negative once the arithmetic on this page is applied.

How much costs actually explain

Most of the gap, when it has been measured. The most active of 66,465 households earned 11.4% a year against a 17.9% market between 1991 and 1996, with the average household turning over 75% of its portfolio annually.[1]

The number is the easy part

Everything above is arithmetic, and anyone opening this page gets the same answer. What no calculator can settle is whether you took the trade on these terms, or are describing — afterwards — the version of it that worked out.

That is what a trade recorder is for: the trade committed before it resolves, timestamped and sealed on the spot, on a Merkle-anchored log a stranger can check without kappi's cooperation. The plan you typed here stops being a plan you remember having. $15/month, no free tier.

Embed this calculator

Paste this into any page. It stays free, needs no account, and links back here.

Sources

  1. Barber & Odean, 'Trading Is Hazardous to Your Wealth', Journal of Finance 55(2), 2000, 773–806 read 2026-08-16

Frequently asked questions

How much do trading fees really cost per year?

Multiply the round-trip cost by your trade frequency. Twenty round trips a month at $7.50 is $1,800 a year — 7.2% of a $25,000 account.

Is slippage bigger than commission?

On most instruments, yes. Commissions are visible and small; slippage is invisible unless measured and frequently exceeds them, especially in less liquid markets.

How do I measure my actual slippage?

Record the price when you send each order, compare it against the fill, and average the difference across at least fifty trades.

What is the most effective way to cut trading costs?

Trade less often. Frequency multiplies every other cost, so halving trade count halves the entire bill without changing anything else.

Let's set some records

Broker-import journals prove what you did after the fact, from data you control. kappi timestamps what you said you would do, before you knew how it would turn out, on a record you cannot edit.

Start a verified track record — $15/mo

No free tier. Cancel any time.

Related