You can read the Japanese stock market in about ten minutes a day if you check seven numbers in the right order — and the single most important habit is never to look at the Nikkei 225 alone. The Nikkei and TOPIX regularly tell different stories, and the gap between them is often the day’s real headline.
Early August 2026 was a textbook case. On August 7, 2026, the Nikkei 225 closed down 0.12% at 65,606.71 on semiconductor selling, while the TOPIX-tracking 1306 ETF — a proxy for the broad index — rose 0.33% to 425.10, with sector ETF proxies showing pharmaceuticals and steel among the leaders. At the same time the yen traded near 158 to the dollar. Days like that are exactly why a fixed checklist beats headline-chasing. What follows is the dashboard we run every session at Tokyo Closing Bell: what each indicator measures, where the official data lives, and how to read it.
1. Nikkei 225 vs TOPIX — and the NT ratio
The Nikkei 225 is price-weighted: high-priced shares such as Fast Retailing, Tokyo Electron, Advantest, and SoftBank Group dominate it regardless of company size. TOPIX is free-float market-cap weighted across the broad Prime market, so banks, autos, and trading houses carry far more influence. The two indices are therefore not interchangeable — they are two different lenses.
The NT ratio (Nikkei divided by TOPIX) compresses the comparison into one number, historically sitting in the mid-teens. A rising NT ratio means leadership is narrowing into the Nikkei’s tech and growth heavyweights; a falling NT ratio means broad domestic value — banks, insurers, autos — is doing the work. Compute the current level yourself from the two official index closes rather than quoting it secondhand — an ETF proxy price is not a substitute for the official TOPIX level in this calculation.
- What it measures: breadth versus concentration of the rally or sell-off.
- Where the data lives: Nikkei Indexes (indexes.nikkei.co.jp/en) for the Nikkei 225; JPX (www.jpx.co.jp/english) for TOPIX.
- Common mistake: reporting a Nikkei-only move as “Japanese stocks fell.” On divergence days, half the market did the opposite.
2. USD/JPY — the market’s second index
A weaker yen inflates the translated overseas earnings of exporters (autos, machinery, tech hardware) and tends to lift the Nikkei; a stronger yen favors importers and domestic demand. But the correlation is regime-dependent: once the yen weakens toward levels where Ministry of Finance intervention becomes plausible — round numbers such as 160 have historically served as watch levels — further weakness can start to hurt equities by raising volatility and import-cost concerns.
USD/JPY trades around the clock, so there is no single official close; watch the level and the speed of the move rather than a to-the-decimal print. As of early August 2026 the pair was trading near 158. The MOF publishes actual intervention records on a regular schedule, which is the only authoritative confirmation — never assume intervention from price action alone.
3. The TSE daily short-selling ratio
Every session, JPX publishes short selling (karauri, selling borrowed shares) as a percentage of total trading value, split into price-rule restricted shorts and exempt shorts (mainly market-making and arbitrage). Two things surprise newcomers: the ratio is published for the previous session, and its normal level is high — historically hovering around 40%, because much of it is structural hedging rather than directional bearishness. The level matters less than the trend and the extremes.
Worked example: reading a real week
Here are the actual JPX figures for five sessions in August 2026:
| Date (2026) | Total short ratio | Restricted | Exempt | Turnover (¥ tril) |
|---|---|---|---|---|
| Aug 3 | 45.4% | 34.1% | 11.3% | 12.52 |
| Aug 4 | 45.3% | 36.1% | 9.2% | 10.93 |
| Aug 5 | 41.8% | 34.2% | 7.6% | 11.68 |
| Aug 6 | 39.9% | 31.9% | 8.0% | 10.34 |
| Aug 7 | 37.1% | 29.2% | 7.9% | 11.52 |
Read it in three steps. First, the level: 45.4% at the start of the window is well above the historical norm of roughly 40% — heavy short-sale activity. Second, the direction: a steady five-session slide to 37.1%, below the week’s average of 41.9%. One plausible reading is that shorts were covering or standing down — selling pressure easing even while the Nikkei chopped sideways — though a falling share can also simply reflect reduced hedging activity, so treat it as a hypothesis rather than a conclusion. Third, the composition: the decline came mostly from the price-rule-restricted bucket. Note that “restricted” is a regulatory classification under the price rule, not a measure of trader intent — it includes hedging as well as directional shorts, so read it alongside other positioning data rather than as a pure bearish-conviction gauge. A falling ratio into a stable tape can be a quietly constructive signal; a rising ratio into a falling tape suggests the down-move still has sponsorship. For depth, Japan Securities Finance data adds squeeze signals: when a large share of loanable issues incurs premium charges (gyaku-hibu, the extra daily fee shorts pay when borrowable stock runs scarce) — as of early August 2026, 500 of 1,113 loanable issues — crowded shorts are getting expensive.
4. The weekly investor-flows report
Once a week, with a lag, JPX publishes trading by investor type (toushi bumon betsu baibai joukyou) for the Prime market. The headline split to watch is foreign investors versus domestic individuals, because foreigners account for roughly two-thirds of trading value and have historically driven the market’s medium-term direction, while retail tends to trade against the trend.
The week of July 27–31, 2026 was a classic print: foreign investors net bought ¥0.37 trillion while individuals net sold ¥0.49 trillion — the familiar mirror image of retail selling into foreign demand. One caution: the MOF’s separate weekly cross-border securities survey showed foreigners net selling ¥0.39 trillion of Japanese equities in the overlapping week. The two series use different reporting bases and reporter samples, so treat any single week as noisy; conviction comes when both point the same way for several weeks. The JPX weekly margin-balance report (margin buying of ¥6.20 trillion versus margin selling of ¥0.73 trillion as of July 31, 2026) rounds out the picture as a retail-leverage gauge.
5. JGB yields — the BOJ-policy thermometer
The Ministry of Finance publishes daily constant-maturity Japanese government bond yields, and they are the cleanest daily read on where markets think Bank of Japan policy is heading. As of August 6, 2026: 2-year 1.565%, 10-year 2.773%, 30-year 3.919%. Read the curve in pieces: the 2-year embeds rate-hike expectations, the 10-year is the broad policy-and-growth gauge, and the super-long end reflects fiscal supply and insurer demand. For equities, rising yields typically support banks and insurers (a structural reason TOPIX can outperform on rate-hike days) while pressuring REITs and long-duration growth stocks. Common mistake: reading JGB yields in isolation from USD/JPY — the US-Japan rate differential ties the two together, and a yield move that narrows the gap usually strengthens the yen.
6. US semiconductor stocks — the overnight lead
Because chip-equipment names carry heavy Nikkei weight, the previous US session — especially the Philadelphia Semiconductor Index (SOX) and the megacap AI complex — is a useful guide to the Tokyo open’s character. A weak US chip session transmits directly into Tokyo Electron, Advantest, Lasertec, Disco, and SCREEN, dragging the Nikkei more than TOPIX and pushing the NT ratio down. The August 7, 2026 session showed the mechanism cleanly: Tokyo Electron fell 1.5% and Advantest 2.25%, while sector ETF proxies — which can deviate slightly from the official TOPIX-17 indices — showed 11 of 17 sectors advancing, led by pharmaceuticals and steel. Check the US close and the equity-futures tone qualitatively before the Tokyo open; the exact decimals matter less than whether chips led or lagged.
7. Three large-cap bellwethers
Three stocks, checked together, tell you which macro force is driving the day (levels as of the August 7, 2026 close):
- Toyota (7203, ¥2,980): the FX-and-global-demand proxy. Toyota outperforming usually means a yen-weakness or global-cyclical day.
- SoftBank Group (9984, ¥5,552): the global tech risk-appetite proxy, driven by its AI and investment portfolio. It often moves with US growth stocks more than with Japan.
- Tokyo Electron (8035, ¥54,500): the chip-cycle proxy and a top Nikkei weight — the bridge between the SOX and the NT ratio.
When all three fall together, the pressure is macro. When they split — Toyota up, Tokyo Electron down — you are looking at rotation, not risk-off, and TOPIX will usually confirm it.
The ten-minute routine
- Previous US close: chips versus the broad tape.
- USD/JPY level and overnight speed.
- Nikkei versus TOPIX; note the NT ratio’s direction.
- Sector board: how many of the 17 TOPIX sectors advanced, and who led.
- Previous session’s short-selling ratio against its recent range.
- JGB yields, especially the 2-year and 10-year.
- The three bellwethers. Weekly, add the investor-flows report.
FAQ
What counts as a “normal” short-selling ratio in Tokyo?
Historically around 40% of trading value, far higher than intuition suggests, because market-making and arbitrage shorts are structural. Readings pushing toward the mid-40s point to heavy short-sale activity, whether hedging or directional; a slide toward the mid-30s is consistent with covering or reduced hedging. Trend and composition beat the raw level.
Why do the Nikkei and TOPIX diverge so often?
Weighting. The price-weighted Nikkei is concentrated in a handful of high-priced tech and growth names, while cap-weighted TOPIX leans toward banks, autos, and domestic demand. A chip-driven sell-off can sink the Nikkei on a day TOPIX rises — which is precisely the information the NT ratio captures.
Is all of this data free?
Yes. JPX publishes the short-selling ratio, investor flows, and margin balances; Nikkei Inc. publishes the Nikkei 225 and Nikkei Volatility Index; the MOF publishes daily JGB yields, weekly cross-border flows, and intervention records; the BOJ publishes policy decisions and money-market data. No paid terminal is required for any indicator on this list.
Sources
- JPX statistics — www.jpx.co.jp/english
- Nikkei Indexes — indexes.nikkei.co.jp/en
- Bank of Japan — www.boj.or.jp/en
- Ministry of Finance Japan — www.mof.go.jp/english
Disclaimer: This is an information and analysis publication, not investment advice. See our Methodology for data sources, standards, and our corrections policy.