JPX-Nikkei Index 400 Futures Contract Specifications (J400)

Equity index futures track a cash index with a fixed dollar multiplier. Because the multiplier is applied to index points, the tick value depends on both the index point size and the increment quoted by the exchange.

Specifications

Margin is not listed here on purpose — the exchange revises it and every broker adds its own buffer. Check your broker's platform for the live figure. Use the margin calculator to estimate what a position will tie up.

Doing the tick math

One tick is 5 in the quoted price, which is ¥500 per contract. A move of one full point (1.00 in the quoted price) is worth ¥100, so there are 0 ticks in a point. Get those two numbers wrong and every risk calculation downstream is wrong, which is the point of the tick value guide.

Enter your own prices in the tick value and P/L calculator to see the dollar result for this contract without doing the arithmetic by hand.

Delivery months

H,M,U,Z — March, June, September, December. Liquidity concentrates in the nearest active month; open interest migrates over a few weeks before expiry, which is what the roll mechanics guide walks through.

What one tick is worth at different position sizes

The per-tick figure scales linearly, which is the part most traders get wrong when they add contracts without re-checking risk.

Ten ticks on a J400 contract is a move of 5 × 10 in the quoted price. If you want the P/L for a specific entry and exit rather than a tick multiple, put the prices into the tick value calculator.

Converting your stop into a dollar risk

Stops are set in price terms but risk is booked in dollars. Multiply the stop distance in ticks by the tick value — and then add commission, which is charged per contract per side and is not in the numbers below.

On a ¥100 X Index Value contract, a 20-tick stop at one contract ties up ¥10,000 of risk before costs. At five contracts it is ¥50,000. This is why position size should follow the stop, not the other way round — the arithmetic is laid out in choosing a futures contract.

How margin is set on JPX-Nikkei Index 400 futures

Margin is not a property of the contract spec — it is a risk parameter the exchange recalculates periodically and that your broker then marks up. Two consequences follow:

• The figure moves when volatility moves, so a margin number copied from a blog post is usually stale.
• Two brokers can require different amounts for the same J400 contract.

What is fixed by the spec is the notional exposure: ¥100 X Index Value multiplied by the price. Margin is a percentage of that notional, which is why a higher price or a wider exchange buffer raises the cash requirement without the contract itself changing. The margin calculator takes your broker's number and converts it into "how many contracts can I hold"; the mechanics are in how futures margin works.

Where these numbers come from

Contract unit, tick size and delivery months are taken from the contract specifications published by Osaka - Japan (JPX). Exchanges occasionally change tick sizes and listing months, so before relying on this page for a live position, check the current spec sheet on the exchange's own product page or on your broker's platform. This page was last rebuilt on 15 November 2026.

What moves JPX-Nikkei Index 400 prices

• Corporate earnings — index level follows aggregate earnings expectations
• Interest rates — the discount rate applied to future earnings
• Concentration — a handful of large constituents can dominate index moves
• Macro releases — inflation, employment and GDP prints move the whole index at once

This is context, not a recommendation. Nothing here tells you which way the market is going.

More stock index contracts

• Nikkei 225 mini (Osaka) (MJNK) — ¥100 X Index Value, ¥500 per tick
• Mini-TOPIX (JMT) — ¥1000 X Index Value, ¥250 per tick
• SGX Nikkei 225 Index (NK) — ¥500 X Index Value, ¥2,500 per tick
• SGX Mini Nikkei 225 Index (NS) — ¥100 x Index Value, ¥100 per tick
• Hang Seng China Ent. Index (HHI) — 50HK$ per index point, HK$50 per tick
• Hang Seng Index (HSI) — 50HK$ per index point, HK$50 per tick

Full list: all 135 contract specifications. Sizing maths: tick value calculator, margin calculator.

Frequently asked

What is the contract size of JPX-Nikkei Index 400 futures?

One J400 contract represents ¥100 X Index Value. Every tick value and point value on this page follows from that quantity.

How much is one tick worth in J400 futures?

One tick is a price move of 5, worth ¥500 per contract. A full point move (1.00 in the quoted price) is worth ¥100.

Which delivery months does J400 trade?

H,M,U,Z — March, June, September, December. The front month carries most of the liquidity and open interest migrates a few weeks before expiry.