Nikkei 225 position size calculator

Size a JP225 trade from your risk and a stop in index points — priced in yen, converted to your account currency, lots rounded down to 0.01.

Updated 31 October 2026

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How sizing works on the Nikkei

JP225 — JPN225 or NI225 at some brokers — is a CFD on Japan's Nikkei 225 index, and it is priced in Japanese yen. The calculator starts from a contract of ¥1 per point per lot, so a point on one lot is ¥1, not $1. On a USD account that yen loss is converted at USDJPY: at the reference rate of 157.14 from 27 September 2026, ¥1 is about $0.0064, and the result is labelled an estimate until you type today's rate. The rate field wants the value of one yen in your currency — 1 ÷ USDJPY, about 0.0064 for a USD account — not the 157.14 quote itself.

A worked example: why the default looks huge

A $10,000 USD account risking 1% has $100 to lose. With a 200-point stop and the default ¥1 contract, one lot loses 200 × ¥1 = ¥200, which is $1.27 at 157.14. The raw size is 100 ÷ 1.2728 = 78.57 lots. That number is only right if your broker's lot really is ¥1 per point.

The Nikkei contract varies by broker — ¥10, ¥100 or more per point instead of ¥1, for example — so check yours in the specification. With ¥100, type 100 in the contract size field: one lot loses ¥20,000 = $127.28 on the same stop, the raw size is 0.786 and the position 0.78 lots, risking $99.27. Same trade, same money, a hundredth of the lots.

Volatility and typical stops

At around 45,000 a 1% move in the Nikkei is 450 points, so intraday stops of 100 to 300 points are common and swing stops run much wider. The index reacts to the yen as well as to stocks: a sharp move in USDJPY or a Bank of Japan decision can move it hard, and the Tokyo open often gaps from the overnight futures price. Because a point is converted at USDJPY, the dollar value of the same stop also changes when the yen moves.

Tokyo hours in New York time and the Kill Zones

Japan does not use daylight saving, so Tokyo is 14 hours ahead of New York in the northern winter and 13 hours in summer. The 09:00 Tokyo open is therefore 19:00 or 20:00 New York time the evening before, and the morning session falls inside the Asian Kill Zone (20:00–00:00 New York). The afternoon session runs into the New York night; the London (02:00–05:00) and New York AM (07:00–10:00) Kill Zones trade on futures. See the windows in your time zone with the Kill Zone converter; today's sessions and news are on the Nikkei 225 market page.

Common Nikkei sizing mistakes

• Keeping the default contract when the broker uses ¥100 per point: the size is then a hundred times too large.
• Typing USDJPY (157.14) into the rate field instead of 1 ÷ USDJPY (0.0064): the position comes out roughly 25,000 times too small.
• Reading ¥1 as $1. On a USD account a point on the default contract is worth less than one cent, so sizing it as a dollar makes the position about 157 times too small.
• Forgetting that the yen moves. A stop sized at USDJPY 150 and the same stop at 157 differ by about 5% in dollars.

For US indices use the NAS100 calculator or the S&P 500 calculator; the method is in how to calculate position size.