The four brokers, side by side
All four are SEBI-registered stock brokers with official trading APIs. This compares what matters to an active trader using those APIs. Prices and plans change, so each broker’s own page is the final word — checked September 2026.
| Zerodha | Dhan | Angel One | Groww | |
|---|---|---|---|---|
| API | Kite Connect | DhanHQ | SmartAPI | Trade API |
| API cost | Personal plan free for orders; live and historical data on the paid Connect plan, per app | Trading APIs free; Data APIs a separate subscription, free for active traders | Free | Paid subscription |
| Daily sign-in | Kite login and TOTP in the browser; the token lasts the trading day | Access token valid for 24 hours | Client code, MPIN and TOTP; the session lasts until midnight | API key approved on Groww’s page each trading day |
| Order IP registration | Manual, in the Kite developer console | By API — one click from QuantumCat | Manual, in the SmartAPI portal | Manual, on Groww’s API keys page |
| Prices in QuantumCat | Live stream | Live stream | Live stream | Polled once a second |
| Depth in QuantumCat | 5 levels | 20 levels (NSE/NFO) | 5 levels | Top of book |
| Broker-side stops in QuantumCat | GTT | Forever orders | GTT (support differs) | Not in this version |
| Hands-free daily sign-in in QuantumCat | Yes | Yes | Yes | Signs in by itself once you approve the key |
How to choose
- You scalp options and read the order book: Dhan is the only one of the four serving 20-level depth, and its trading APIs are free.
- You already trade on Zerodha: stay. Kite Connect is free for orders; take the paid Connect plan for live and historical data, and let QuantumCat handle the daily Kite login.
- You want the lowest API cost: Angel One’s SmartAPI is free, within the segments your account is enabled for.
- Your money is already on Groww: it works — with prices polled once a second, Groww’s daily key approval and no broker-side standing orders in this version, so keep carry stops in Groww’s own app.
- Brokerage itself: compare each broker’s current tariff for your segment — intraday, F&O and delivery are priced differently — while taxes such as STT and stamp duty are the same at every broker.
The terminal matters as much as the broker
Your broker executes orders and holds your money. How well you trade depends on the tools on top: whether you see your real fill before you click, size from risk, keep stops at the broker, test ideas honestly and can flatten everything in one move.
QuantumCat runs on all four brokers, through each broker’s official API, on your own account. Your money and securities never move — no new demat, no transfers — and orders travel from your machine straight to your broker, with no QuantumCat server in between. Pick your broker on cost and features, keep the same terminal, shortcuts and risk rules if you ever switch — or run two brokers side by side, each position pinned to the account that holds it.
Broker pages: QuantumCat for Zerodha · for Dhan · for Angel One · for Groww. Connecting a broker takes a few minutes — see the setup guide.
Questions
Which is the best broker in India for options trading?
For an active options trader, Dhan stands out for 20-level depth and free trading APIs; Zerodha if you already trade on Kite; Angel One for a free API; Groww if your money is already there. Whichever you choose, QuantumCat adds an option chain with greeks computed from the chain’s own IV, a strategy lab with payoff and margin, fill preview for your size and broker-side stops where the broker supports them.
Which broker has the best API for algo trading in India?
Dhan’s trading APIs are free and serve 20-level depth; Kite Connect is free for orders, with market data on a paid plan; Angel One’s SmartAPI is free; Groww’s is a paid subscription with no published live socket. All four work with QuantumCat.
Is Zerodha Kite Connect free?
Partly. Kite Connect’s Personal plan is free for placing orders and reading your account; live and historical market data need the paid Connect plan, billed per app (per API key). Check developers.kite.trade for current pricing.
Can I use QuantumCat with Upstox or Fyers?
Not yet. QuantumCat supports Zerodha, Dhan, Angel One and Groww today; Upstox and Fyers are next.
Does QuantumCat hold my money or execute my trades?
No. QuantumCat is software, not a broker. Your money and securities stay with your broker, which executes every order under your own credentials; QuantumCat sends each order from your machine through the broker’s official API.
Education, not investment advice. QuantumCat is software, not a SEBI-registered investment adviser or research analyst, and nothing on this page is a recommendation to buy or sell any security. Figures from SEBI and the brokers are linked to their sources; broker prices and plans change, so check each broker's own page.