GER40, UK100 and JP225 Lot Size: Sizing Indices Not Priced in Dollars
The US index guide covers US30 and NAS100, where a point is worth dollars and a dollar account needs no conversion. Europe and Asia add one step: the point is worth euros, pounds or yen, and your risk is probably in something else.
Check the contract first
Same problem as US indices: brokers don't agree on what one lot is.
- GER40 (DAX): usually €1 per point per lot. Some brokers use €25 (futures-style) or €0.10.
- UK100 (FTSE 100): usually £1 per point per lot.
- JP225 (Nikkei): all over the place. ¥100 per point is common, ¥1 and ¥10 exist.
Open the contract specification in your platform. If the "contract size" is 1 and the quote currency is EUR, that's €1 a point.
The formula
Lots = risk ÷ (stop in points × value per point, converted to your account currency)
Convert either side. Just don't divide dollars by euros.
GER40 with a USD account
- Account: $10,000, risking 1% = $100
- Entry 19,200, stop 19,150: 50 points
- €1 per point per lot: €50 per lot
- EUR/USD at 1.0800: €50 = $54 per lot
$100 ÷ $54 = 1.85 lots.
Assume $1 a point instead and you get 2.00 lots, risking $108. Not dramatic. Do it every trade on a tight daily limit and it is.
UK100 with a GBP account
- Account: £5,000, risking 1% = £50
- Entry 8,300, stop 8,270: 30 points
- £1 per point per lot: £30 per lot
£50 ÷ £30 = 1.66 lots. Account and index in the same currency, so nothing to convert. This is the easy case.
JP225 with a USD account
- Account: $10,000, risking 1% = $100
- Entry 38,500, stop 38,350: 150 points
- ¥100 per point per lot: ¥15,000 per lot
- USD/JPY at 150.00: ¥15,000 = $100 per lot
$100 ÷ $100 = 1.00 lot.
If your broker uses ¥1 per point, the same trade is 100 lots. That's not a typo. It's why you check the contract spec first. The calculator's JP225 page starts at ¥1 per point, so set your broker's contract size before reading the lot size.
When they move
These indices are quiet until their home market opens, then they aren't.
- GER40: the cash open at 09:00 Frankfurt is the big one.
- UK100: the 08:00 London open.
- JP225: the Tokyo session, plus sharp moves when USD/JPY moves.
A stop that fits the overnight range can be far too tight for the open. Wider stop, smaller lots, same risk.
Quick version
- Find value per point per lot in the contract spec.
- Stop in points × value per point = risk per lot, in the index currency.
- Convert to your account currency at today's rate.
- Lots = risk ÷ that number, rounded down.
The calculator has GER40, UK100 and JP225 pages with an editable contract size and live conversion rates. Account not in dollars? See sizing with a non-USD account.