> Source: https://ashareapi.com/en/docs/guides/main-capital-flow/  ·  Markdown version for LLMs / AI agents

Tutorial

# Reading main capital flow in A-shares
 Money flow is not a price predictor — it is a thermometer for participation and the direction of chips. One `/v1/fund` request returns main-capital inflow (today / 5 / 10 / 20-day) + market rank + top-trader detail. The hard part is reading it; code and four common misreadings below.

## What one request gives you

 Python (key required)
```
import requests

KEY = "ct-your-key"
r = requests.get("https://api.ashareapi.com/v1/fund",
 headers={"Authorization": "Bearer " + KEY},
 params={"code": "sh600667"}, timeout=30)
d = r.json()["data"]

print(d["date"], d["close"]) # 2026-09-24 19.41
print("today ", d["main_net"]) # -528559730.00
print("5-day ", d["main_net_5d"]) # -571025057.00
print("10-day ", d["main_net_10d"]) # 531599448.00
print("20-day ", d["main_net_20d"]) # -82259566.00
print("market rank", d["main_rank"]) # 5532
```

-
 **The payload is an object** (not an array): `main_net*` / `main_rank` / `lhb` / `lhb_details` / `block_trades` / `margin`

-
 Amounts are in **CNY** and arrive as **strings** (`"-528559730.00"`) — cast to float before comparing

-
 `main_rank` is the **market-wide net-inflow rank** (larger = further toward net outflow)

-
 The same call also returns **top-trader boards, block trades and margin data** — no extra endpoints needed

## Read the four horizons together
 **One day lies.** A single session is noise; the four horizons together carry the signal:

-
 **Rank beats absolute value**: 100M of inflow ranked #10 is nothing like ranked #3000

-
 `industry_rank` is the within-industry rank; in our measurement it returned `0`, meaning **the figure was unavailable that day** — not "ranked 0"

 |
| | Pattern | How to read it | Watch out

| | today −, 5/10/20-day + | Short-term pullback, medium-term inflow intact | Worth watching, not a reason to buy

| | today +, 5/10/20-day − | A bounce pulse while the medium term bleeds | **Caution**: looks like distribution into strength

| | all four + | Sustained inflow | Strongest shape — but check price keeps up

| | all four − | Sustained outflow | Weak; "it has fallen a lot" is not a reason

| | today + but rank low | Inflow, yet many names are stronger | Relative strength is weak — do not read absolute numbers alone

 today −, 5/10/20-day +
 Short-term pullback, medium-term inflow intact
 Worth watching, not a reason to buy

 today +, 5/10/20-day −
 A bounce pulse while the medium term bleeds
 **Caution**: looks like distribution into strength

 all four +
 Sustained inflow
 Strongest shape — but check price keeps up

 all four −
 Sustained outflow
 Weak; "it has fallen a lot" is not a reason

 today + but rank low
 Inflow, yet many names are stronger
 Relative strength is weak — do not read absolute numbers alone

## Top-trader boards: institutions or hot money?
 `lhb` is the summary (reason / total buy / total sell / net buy); `lhb_details` is the **seat-level detail** (up to 10 rows) — the key to "who is trading".

 Python (key required)
```
for x in d["lhb"]:
 print(x["Reason"], "| buy", x["TotalBuy"], "| sell", x["TotalSell"], "| net", x["NetBuy"])
# measured: cumulative 20% deviation over 3 sessions | buy 2.177B | sell 2.570B | net -393M

for x in d["lhb_details"]:
 side = "buy" if x["Buy"] else "sell"
 print(f'{x["RankType"][:6]} #{x["Rank"]} {x["Name"]} {side} {x["Buy"] or x["Sell"]}')
# measured (sh600667, 2026-09-24):
# sell seat #5 UBS Shanghai Huayuanshiqiao Rd sell 279M
# sell seat #3 Goldman Sachs Shanghai Century Ave sell 487M
# sell seat #2 Guotai Haitong HQ sell 565M
```

-
 **The seat name is the signal**: known hot-money seats are short-term money; "institution" seats are funds

-
 **Look at the net direction**: when both sides appear, compare **net buy**, not "on the board = bullish"

-
 `HotMoneyTags` flags hot-money tags (empty string in our measurement = none)

-
 **Being on the board is an outcome, not a cause**: it means the stock already moved sharply; chasing then often means buying the top

## Block trades and margin, in the same call

 Python (key required)
```
print("block trades", len(d["block_trades"]))
print("margin", len(d["margin"]))
# measured on sh600667: both are empty arrays [] -> no such data that day
# NOTE: an empty array is not a failure — just nothing on file for this stock
```

-
 **Block-trade discount** = someone sold below market (bearish short term); **premium** = someone paid up to buy

-
 **Rising margin balance** = leveraged longs (and a bigger stampede risk on a pullback)

-
 For dedicated views use `/v1/block-trade` and `/v1/margin-trade` (the latter supports batched codes)

## Four common misreadings

-
 **"Inflow means it will rise"** — wrong. Flow is coincident or lagging: inflow with a flat price (accumulation) and outflow with a rising price (distribution) both happen

-
 **Reading one day only** — single-session noise is huge; look at least at the 5-day

-
 **Treating rank as a verdict** — rank is **relative**; in a bear market even #100 can be net selling

-
 **Ignoring how "main" is defined** — it usually means large/block orders, and thresholds differ by platform. We give a **consistent multi-horizon series**, so comparing across time and names is safer than raw absolutes

## Boundaries (stated so you do not misuse it)

-
 **No northbound flow intraday** — there is no market-wide northbound endpoint

-
 **No minute-level flow** (we do not do minute data)

-
 **No market-wide flow ranking table** — `main_rank` is one stock’s rank among all stocks, not a list you can dump

-
 **Key required** — `/v1/fund` is a paid endpoint; the top-trader split `/v1/lhb` is paid too (type=institution/hotmoney/activeseat)

-
 **Not investment advice** — how to fetch and how to read, not what to buy

## FAQ
 If main-capital inflow is positive, will the stock rise?
 **No.** Flow is coincident or lagging: "inflow with a flat price" (accumulation) and "outflow with a rising price" (distribution) are both common. Its value is **cross-validation** alongside price, top-trader boards and volume — not standalone prediction.

 What is the difference between main_rank and industry_rank?
 `main_rank` is the **market-wide** net-inflow rank (5532 for sh600667 in our measurement, i.e. toward the outflow side); `industry_rank` is the within-industry rank. Note that `industry_rank` returned `0` in our measurement, meaning **the figure was unavailable that day** — not "ranked 0".

 Are empty block_trades / margin arrays an error?
 **No.** An empty array means there was no block-trade or margin data for that stock on that date. For market-wide or date-specific views, use `/v1/block-trade` and `/v1/margin-trade`.

 How often does money-flow data update?
 Main-capital flow and top-trader boards update **per trading day** (after the close). The `date` field tells you which session the data belongs to (2026-09-24 in our measurement) — **check it before interpreting**; intraday you are still looking at the previous session.

 Can I rank every stock by money flow?
 **No.** `/v1/fund` is **per code** (it returns that stock’s market rank), not a market-wide list endpoint. To rank a basket, prepare your own code list and loop (mind the rate limits).

 Last updated: 2026-09-25
 Fields and values come from live responses (measured 2026-09-25 on sh600667: main_net -528559730.00 · 5-day -571025057.00 · 10-day 531599448.00 · 20-day -82259566.00 · main_rank 5532 · industry_rank 0 · lhb 1 row · lhb_details 10 rows · block_trades and margin both empty arrays). The "main capital" definition (large/block order thresholds) is set by each data platform; this service provides a consistent multi-horizon series.

 Read next

-
[Endpoint reference (fund / lhb / block-trade / margin-trade)](/en/endpoints)

-
[A-share top-trader boards with Python: four approaches](/en/docs/guides/longhubang-data)

-
[Financial red flags: three-statement cross-checks](/en/docs/guides/financial-redflags)

-
[Error codes & rate limits](/en/docs/errors)

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