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Ledgerworks Institute

Tools

Instruments for working through the arithmetic.

Both tools below run in your browser on figures you supply. They are built to make a cost or a constraint visible — not to model a market, and not to suggest a position. Nothing is submitted, nothing is stored, and you are never asked to connect a wallet.

  • Free to use
  • No account required
  • Nothing leaves your browser
01Execution cost

Fee and slippage calculator

Execution cost is four separate things that behave differently. Kept apart, each can be reasoned about; lumped together, they turn into a vague sense that trading "costs a bit". Put your own figures in and the break-even move at the bottom stops being abstract.

The notional value you intend to transact.

Half of this is charged when you cross to the other side.

How far your own order moves the price as it consumes depth. Your estimate, not ours.

Cost of the trade

Spread (half, one side)
$4.00
Market impact
$5.00
Venue fee
$10.00
Network fee
$2.50
One way, total
$21.50
One way, in basis points
21.5 bps
Round trip (in and out)
$43.00

On these figures the position has to move 0.43% in your favour before the round trip breaks even. That threshold is the point of the exercise: it is a cost you pay with certainty, against an outcome you do not control.

02Risk arithmetic

Position-sizing worksheet

Sizing is a constraint, not a forecast. Given an account, a share of it you accept losing, and the price at which your reason for holding no longer applies, the size follows arithmetically. The worksheet does that arithmetic and shows what the loss would cost you to undo.

The whole account, not the amount you intend to deploy.

The share of the account you accept losing if the position is invalidated.

Invalidation is the price at which the reason for holding no longer applies. Choosing it is an analytical judgement the worksheet cannot make for you — it only does the arithmetic that follows.

The arithmetic

Amount at risk
$250.00
Risk per unit
$5,000.00
Distance to invalidation
7.81%
Position size
0.05 units
Notional exposure
$3,200.00
Exposure as % of equity
12.8%

If this position is lost in full, equity becomes $24,750.00, and returning to where you started then requires a gain of 1.01% on the smaller balance. The asymmetry is the whole lesson: losses and the gains that undo them are not the same size.

The recovery asymmetry

A loss and the gain that reverses it are not the same size, because the gain is earned on a smaller balance. This is arithmetic, not a market claim — it holds identically for every asset and every method.

Gain required to recover from a given drawdown
DrawdownGain needed to recover
−10%+11.1%
−20%+25.0%
−33%+49.3%
−50%+100.0%
−75%+300.0%

What these tools are not.

Neither tool fetches a price, connects to an exchange or knows anything about any asset. They take the numbers you type and do arithmetic on them. A result is therefore a statement about your inputs and nothing else — it is not a recommendation, a valuation, or a prediction, and a sensible-looking output from careless inputs is still careless.

The portfolio ledger described in the catalogue is part of full access and is not published on this page. What is here is what you can use right now, without an account.

Educational disclaimer

Ledgerworks Institute provides educational content and learning tools only. Nothing on this platform constitutes financial advice, an investment recommendation, or a guarantee of any outcome. Cryptocurrency and digital-asset markets carry substantial risk, including the total loss of capital. Conduct your own research and consult a qualified, licensed professional before making any financial decision.

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