KOSPI market cap by company
Every KOSPI constituent — 825 companies — ranked by market cap and by share of total market value on 2026-10-29. Free, in English, company-level. The two largest are 52.3% of the market between them.
Read this before the table: it is not the index weight
People search for “KOSPI weights” and mean the numbers used to build the index. This page is not that. The index is constructed on free-float adjusted market capitalisation, which discounts shares that cannot trade. We do not hold the float factors, so we publish what we can compute honestly: a company’s full market capitalisation as a share of the sum of all of them. For a company with a large locked-in stake the two figures differ, and in one direction — the unadjusted share is the higher one.
This is data, not advice. Nothing here says a company is cheap, expensive, over-weighted or under-weighted, and no averages are computed.
The twenty-five largest
| # | Company | Industry | Value (₩tn) | Share | Cumulative |
|---|---|---|---|---|---|
| 1 | SAMSUNG ELECTRONICS CO,.LTD | Electronic Components, Computers, and Communication Equipment | 1,356 | 28.71% | 28.7% |
| 2 | SK hynix Inc. | Electronic Components, Computers, and Communication Equipment | 1,115 | 23.59% | 52.3% |
| 3 | SK Square Co., Ltd. | Financial Services | 126 | 2.66% | 55.0% |
| 4 | SAMSUNG ELECTRO-MECHANICS CO.,LTD | Electronic Components, Computers, and Communication Equipment | 96.6 | 2.04% | 57.0% |
| 5 | LG ENERGY SOLUTION, LTD. | Electrical Equipment | 83.3 | 1.76% | 58.8% |
| 6 | SAMSUNG BIOLOGICS CO.,LTD. | Medicinal Substances and Pharmaceuticals | 63.2 | 1.34% | 60.1% |
| 7 | HYUNDAI MOTOR CO | Motor Vehicles and Trailers | 59.5 | 1.26% | 61.4% |
| 8 | KB Financial Group Inc. | Financial Services | 55.6 | 1.18% | 62.5% |
| 9 | Samsung Life Insurance co., Ltd | Insurance and Pension Funding | 55.6 | 1.18% | 63.7% |
| 10 | SAMSUNG C&T CORPORATION | Wholesale Trade and Commission Trade | 52.5 | 1.11% | 64.8% |
| 11 | Celltrion, Inc. | Medicinal Substances and Pharmaceuticals | 43.9 | 0.93% | 65.8% |
| 12 | SAMSUNG SDI CO.,LTD | Electrical Equipment | 43.4 | 0.92% | 66.7% |
| 13 | KIA CORPORATION | Motor Vehicles and Trailers | 42.3 | 0.89% | 67.6% |
| 14 | SHINHAN FINANCIAL GROUP CO.,LTD | Financial Services | 41.5 | 0.88% | 68.5% |
| 15 | HANWHA AEROSPACE CO., LTD. | Other Transport Equipment | 39.2 | 0.83% | 69.3% |
| 16 | SK Inc. | Financial Services | 38.8 | 0.82% | 70.1% |
| 17 | DOOSAN ENERBILITY CO., LTD. | Other Machinery and Equipment | 36.3 | 0.77% | 70.9% |
| 18 | Hana Financial Group Inc. | Financial Services | 32.4 | 0.69% | 71.6% |
| 19 | HYUNDAI MOBIS CO.,LTD | Motor Vehicles and Trailers | 31.7 | 0.67% | 72.2% |
| 20 | SAMSUNG FIRE & MARINE INSURANCE CO.,LTD | Insurance and Pension Funding | 29.1 | 0.62% | 72.8% |
| 21 | HD HYUNDAI HEAVY INDUSTRIES CO.,LTD. | Other Transport Equipment | 28.5 | 0.60% | 73.4% |
| 22 | NAVER Corporation | Information Services | 26.6 | 0.56% | 74.0% |
| 23 | LG ELECTRONICS INC. | Electronic Components, Computers, and Communication Equipment | 25.3 | 0.54% | 74.5% |
| 24 | LS ELECTRIC CO., LTD | Electrical Equipment | 23.8 | 0.50% | 75.1% |
| 25 | Woori Financial Group Inc. | Financial Services | 22.7 | 0.48% | 75.5% |
Company-level: a firm whose preferred shares list separately is counted once, under its regulatory filing identity. Ranking by listed line instead would put one company in the table twice and push the genuine 25th off the bottom.
How the market is distributed
A distribution, not an average. Each band shows how many companies fall in it and how much of total market value they hold together.
| 5% or more | 2 | 52.3% of value | |
|---|---|---|---|
| 1% to 5% | 8 | 12.5% of value | |
| 0.5% to 1% | 14 | 10.2% of value | |
| 0.1% to 0.5% | 68 | 16.2% of value | |
| under 0.1% | 733 | 8.7% of value |
Read the top and the bottom row together. The handful of companies above 5 percent hold 52.3% of the market; the 733 companies under 0.1 percent hold 8.7%. An index that looks like a broad market by company count is, by value, a small number of names.
Concentration, stated plainly
| Largest | Share of total market value |
|---|---|
| 2 companies | 52.3% |
| 5 companies | 58.8% |
| 10 companies | 64.8% |
| 30 companies | 77.8% |
| 50 companies | 84.3% |
| 100 companies | 92.0% |
5 KOSPI companies have no market capitalisation on this date. They are left out of the denominator rather than entered as zero, so the shares above sum across 825 companies.
Related
The same companies with price-earnings, price-book and return-on-equity figures are on the Korea valuation tape. Ranked four different ways by size — value, revenue, assets and operating profit — on the largest companies in Korea. See what else is in the catalogue.
Questions
Does the new accounting standard change these weights?
Not the weights — they are built from market value, which the standard does not touch. But any earnings figure shown alongside them is on the pre-1118 basis. Korea adopts K-IFRS 1118 (the local form of IFRS 18) for fiscal years beginning on or after 1 January 2027, which redefines operating profit and restates prior years. We note it here so the two sets of numbers are not read as one.
Is this the KOSPI index weight?
No, and the difference matters. The KOSPI index is built on free-float adjusted market capitalisation, which discounts shares that are not available to trade. This page divides full market capitalisation by the sum of full market capitalisations. For a company with a large locked-in holding the two numbers differ. We publish the one we can actually compute and name it for what it is.
What share of KOSPI is Samsung Electronics?
SAMSUNG ELECTRONICS CO,.LTD is 28.71 percent of total KOSPI market value on 2026-10-29, at 1,356 trillion won. The second largest, SK hynix Inc., is 23.59 percent. Together the two are 52.3 percent.
How concentrated is the KOSPI?
The five largest companies hold 58.8 percent of total market value, the ten largest 64.8 percent and the fifty largest 84.3 percent. The 525 companies outside the top 300 hold 1.66 percent between them.
How many companies are on the KOSPI?
825 companies have a market capitalisation on 2026-10-29 in this dataset. 5 more are listed but have no figure that day and are left out of the denominator. Counting is by company, not by listed line: a firm whose preferred shares list separately is counted once.
Where does the data come from and is it free?
It is free and in English. Market capitalisation comes from the Korean government public data portal daily price dataset for 2026-10-29; company identity and industry come from the Korean Financial Supervisory Service DART filings.
Sources, and what this cannot tell you
Market capitalisation: Korean government public data portal daily price dataset, 2026-10-29. Company identity and industry: DART filings, Financial Supervisory Service. Built 30 October 2026, 20:10 KST.
It cannot tell you the index weight, because that needs free-float factors we do not hold. It is one trading day, so it moves. It says nothing about what any company is worth or what anyone should do. This is not investment advice.
Citing this page. Please cite as SeoulMarkets, KOSPI market cap by company — every constituent ranked, free and in English, 2026, https://seoulmarkets.com/data/kospi-weights — and if a number here is wrong, tell us.