Last updated: October 8, 2026

This page explains how the calculators and guides on TachiTrade work: the formulas we use, where our data comes from, and where the results can differ from your broker. I want you to be able to check my numbers yourself.

1. How the calculators work

Our calculators run in your browser. The numbers you type in are not sent to our servers (see our Privacy Policy).

2. The formulas

Position size (lot size)

Risk amount = Account balance × Risk %
Lot size = Risk amount ÷ (Stop-loss in pips × Pip value per 1 lot)

We round the lot size down to your broker’s lot step (for example 0.01), so your real risk never goes above the amount you chose.

Pip value

Pip value per lot = Pip size × Contract size

For most forex pairs, 1 pip is 0.0001 and 1 standard lot is 100,000 units. For pairs with the Japanese yen, 1 pip is 0.01. The result is in the pair’s quote currency, and we convert it to your account currency using an exchange rate.

Gold (XAUUSD)

Brokers do not agree on what a “pip” is for gold, so we show the value of a clear $1 price move as well. With a contract size of 100 ounces, a $1 move is worth $100 per 1 lot. You can match the result to your broker’s own pip or point size and contract size.

Margin

Required margin = (Lots × Contract size × Price) ÷ Leverage

The result is converted to your account currency.

Risk and reward

Risk:reward ratio = Reward distance ÷ Risk distance
Break-even win rate = 1 ÷ (1 + Risk:reward ratio)
Expectancy per trade = (Win rate × Average win) − (Loss rate × Average loss)

Drawdown recovery

Gain needed to recover = Loss % ÷ (1 − Loss %)

For example, a 20% loss needs a 25% gain to get back to where you started.

Prop firm tools

Daily loss limit = Base balance × Daily loss %
Static drawdown floor = Starting balance − Maximum loss
Trailing drawdown floor = Highest balance (or equity) − Maximum loss

Firms differ in which balance they use, when the day resets, and whether the drawdown is static or trailing. Our tools let you choose the rule that matches your account.

3. Our data sources

  • Exchange rates: some calculators use rates from a third-party data provider. These are reference rates, may be delayed, and are not live trading prices.
  • Prop firm rules: we take rules from the firm’s official website and show the date we last checked them. Rules change often, so always confirm them with the firm before you buy.
  • Contract sizes and pip definitions: we use common industry standards. Your broker may use different ones.

4. Where results can differ from your broker

Calculator results are estimates. They can differ from your real trades because of:

  • spreads, commissions and swaps;
  • slippage and price gaps;
  • your broker’s contract size, minimum lot, lot step and rounding;
  • leverage limits and margin rules that vary by account and country; and
  • exchange rates that move between the time you calculate and the time you trade.

Always check the numbers on your broker’s platform before you place a trade. Read our Risk Disclaimer.

5. How we check our work

  • Each calculator is tested against real figures from a broker platform before it goes live.
  • We show a worked example on the page so you can repeat the calculation by hand.
  • When a broker or prop firm changes a rule, we update the page and the “last verified” date.

6. Independence

Our calculators give the same result to everyone. They do not depend on any partner or on any commission. We explain how the site earns money in our Affiliate Disclosure, and you can read more about me on the About page.

7. Report a mistake

If you think a result or a rule is wrong, email tachiteam@gmail.com with the tool name and the numbers you used. I will check it and fix it if needed.