Contract rules. Lot sizes, expiry dates, holidays and charges use the listed schedules.
How the Paper Trading market works
How prices are made, how orders fill, which charges apply and where your money and trades are saved.
How it works, in short
Options use the price model from Market X-Ray: Premium. Orders meet the bid or ask after the next quote. Lot sizes, expiry days, holidays and charges follow the listed rules. Collateral is checked before an order is accepted. Your money and trades are saved in this browser. Read the assumptions below to understand each figure.
Same setup, same market. A replay with the same setup plays the same market again.
If something breaks, the market pauses. It shows no result rather than a wrong one.
Your money and trades stay in this browser. You can save them as a backup file.
Settings of the market
Contract rules
Lot sizes, the Tuesday expiry day, session timings, holidays and charges follow the market's published rules. The strike interval and the price tick are below, with their source and the date they were last checked.
| NIFTY | 50 |
|---|---|
| BANKNIFTY | 100 |
| Price tick, rupees | 0.05 |
| Last read from the exchange page on | 2026-09-14 |
Source: https://www.nseindia.com/static/products-services/equity-derivatives-contract-specifications
| NIFTY weekly option expiries listed | 4 |
|---|---|
| Monthly option and futures expiries listed | 3 |
| Extra quarterly option expiries listed | 2 |
Price settings
| Starting levels | NIFTY 24,000 · BANKNIFTY 52,000 |
|---|---|
| Starting implied volatility, percent | 16 |
| Risk-free rate used, percent | 7 |
| Dividend yield used, percent | NIFTY 0.6 · BANKNIFTY 0.1 |
| The market pauses if implied volatility leaves this range, percent | 1 – 400 |
| The market pauses if the spot rises or falls this many times away from its starting level | 4× |
| Realised-volatility scale, multiple of the scenario's IV (NIFTY / BANKNIFTY) | 0.9592 / 1.0988 |
| Implied-volatility scale, multiple of the scenario's IV (NIFTY / BANKNIFTY) | 1 / 1.11 |
| Realised divided by implied, as designed (NIFTY / BANKNIFTY) | 0.96 / 0.99 |
| Realised divided by implied, as measured from one close to the next (NIFTY / BANKNIFTY) | 0.93 / 0.96 |
Spot moves use a lower volatility than option IV. In calm markets, this gives sellers a small edge on average. Buyers pay for more movement than the path delivers. Planned shocks and gaps can reverse that edge. Read this assumption with the results.
Fill settings
| Depth levels quoted per side | 3 |
|---|---|
| Base depth at the touch, lots (options / futures) | NIFTY 8–27 · BANKNIFTY 1.7 / 12 |
| Used-up depth comes back after this many market updates | 4 |
| Flat brokerage per order (an assumption), rupees | 20 |
Charges on a paper trade
Each fill is charged from the schedule below, as it stood on the trade date. Every row names its source. One line is different. The tax on an option exercised at expiry uses an assumed rate, and it is marked assumed.
Schedule in force on 2026-01-05
| Charge | Applies to | Rate | Source |
|---|---|---|---|
| Securities Transaction Tax (STT) | on the sell value · sell side · intraday or carried | 0.1 percent of basis | cited from the site's fee table · STT on sale of an option in securities: 0.1% of option premium, w.e.f. 1 Oct 2024 (Finance (No.2) Act, 2024, raised from 0.0625%). Exercised options are charged differently - see the page notes. SUPERSEDED from 1 Apr 2026 - see the successor rule below. · 2024-10-01 |
| Stamp duty | on the buy value · buy side · intraday or carried | 0.003 percent of basis | cited from the site's fee table · Uniform stamp duty on derivatives (options), 0.003% of premium on the buy side, w.e.f. 1 Jul 2020 (Indian Stamp Act amendment). · 2020-07-01 |
| Exchange transaction charge | on turnover · both sides · intraday or carried | 3,503 per crore | cited from the site's fee table · NSE transaction charges, equity derivatives (options): Rs 3,503 per crore of premium turnover, w.e.f. 1 Oct 2024 (NSE/FA/64323, 27 Sep 2024). SUPERSEDED from 1 Mar 2026 - see the successor row. · 2024-10-01 |
| Investor Protection Fund (IPFT) | on turnover · both sides · intraday or carried | 50 per crore | cited from the site's fee table · NSE Investor Protection Fund Trust levy, equity-derivatives options: Rs 50 per crore of premium turnover (Rs 0.01 base + Rs 49.99 corpus top-up from 1 Apr 2023, NSE/FA/56129). ROLLED BACK from 1 Mar 2026 - see the successor row. · 2023-04-01 |
| SEBI turnover fee | on turnover · both sides · intraday or carried | 10 per crore | cited from the site's fee table · SEBI turnover fee: Rs 10 per crore of premium turnover (derivatives). · 2024-01-01 |
| GST (18%) | on the charges GST applies to · both sides · intraday or carried | 18 percent of basis | cited from the site's fee table · GST on stock-broker services, 18% of brokerage plus transaction charges. · 2024-01-01 |
| Charge | Applies to | Rate | Source |
|---|---|---|---|
| Securities Transaction Tax (STT) | on the sell value · sell side · intraday or carried | 0.02 percent of basis | cited from the site's fee table · STT on the sale of a futures contract: 0.02% of the price at which the future is traded, w.e.f. 1 Oct 2024 (Finance (No.2) Act, 2024, raised from 0.0125%). The buy leg pays no STT. SUPERSEDED from 1 Apr 2026 — see the successor row. · 2024-10-01 |
| Stamp duty | on the buy value · buy side · intraday or carried | 0.002 percent of basis | cited from the site's fee table · Uniform stamp duty on derivatives (futures), 0.002% of the traded value on the buy side, w.e.f. 1 Jul 2020 (Indian Stamp Act amendment). Rates were state-specific before that date. · 2020-07-01 |
| Exchange transaction charge | on turnover · both sides · intraday or carried | 173 per crore | cited from the site's fee table · NSE transaction charges, equity derivatives (futures): Rs 173 per crore of traded value, w.e.f. 1 Oct 2024 (NSE/FA/64323, 27 Sep 2024). SUPERSEDED from 1 Mar 2026 — see the successor row. · 2024-10-01 |
| Investor Protection Fund (IPFT) | on turnover · both sides · intraday or carried | 10 per crore | cited from the site's fee table · NSE Investor Protection Fund Trust levy, equity-derivatives futures: Rs 10 per crore of traded value (Rs 0.01 base + Rs 9.99 corpus top-up from 1 Apr 2023, NSE/FA/56129). ROLLED BACK from 1 Mar 2026 — see the successor row. · 2023-04-01 |
| SEBI turnover fee | on turnover · both sides · intraday or carried | 10 per crore | cited from the site's fee table · SEBI turnover fee: Rs 10 per crore of traded value (derivatives). · 2024-01-01 |
| GST (18%) | on the charges GST applies to · both sides · intraday or carried | 18 percent of basis | cited from the site's fee table · GST on stock-broker services, 18% of brokerage plus transaction charges. · 2024-01-01 |
| Assumed STT on an exercised option, percent of intrinsic value | 0.125 — assumed — not a cited rule |
|---|---|
| Settlement price source | Market settlement value |
How collateral is worked out
| Spot shocks, percent of spot | -6, -4, -2, 0, 2, 4, 6 |
|---|---|
| Implied-volatility multipliers | 0.8, 1, 1.2 |
| Stress scenarios per index | 21 |
| Uncovered short tail floor, percent of notional | 3 |
| Cross-index offset | no |
Steps, in order
Stress grid: the whole book of one index is repriced at every pair of spot shock and IV multiplier. The worst loss is the grid figure.
Stress grid spot shocks, percent -6, -4, -2, 0, 2, 4, 6 IV multipliers 0.8, 1, 1.2 scenarios 21 book repriced jointly within an index yes Exact terminal risk: the worst loss at expiry for each group with the same expiry, inside the stress range. It is measured from the current mark, with no credit between expiries.
Exact terminal risk measured from the current mark, not the price the position was opened at evaluated at every strike inside the stress range plus its two edges credit between expiries no Unbounded floor: every net-short option unit whose tail no later long covers adds a percent of its strike notional.
Unbounded floor floor, percent of notional 3 what counts as cover a long of the same right with the same or a later expiry, any strike futures treated as their option pair yes Combine: for each index, take the larger of the grid figure and terminal risk plus floor. Then add the indices together.
Combine rule the larger of the grid figure and terminal risk plus floor then summed over indices yes Pending order reserve: a resting order holds what its fill would take from your free money. That is its net debit and charges, less the value it brings in, plus its collateral change. It is never less than its net debit and charges. So a bought option holds its cost and charges once. It holds them until it fills or is cancelled.
Pending order reserve rule what the fill would take from free money, never less than net debit and charges stored on the order's own reserve figure
What collateral excludes
- No liquidity buffer. A broker adds margin for contracts that are hard to exit. This estimate does not.
- No concentration buffer. A broker charges more when one strike or expiry dominates a book. This estimate does not.
- No calendar-spread charge. The exchange adds a margin between different expiries of the same right. This estimate does not.
- Not the exchange's SPAN parameters. The exchange publishes its own risk arrays and price scan ranges. This estimate uses its own stress grid.
- No broker exposure margin. Brokers add an exposure margin on top of SPAN. This estimate does not.
- No intraday margin benefit. A broker may ask for less on positions closed the same session. This estimate never does.
Value charts: scenario and timeline
The current-value scenario reprices every open leg at a spot, IV and time you choose. The multi-expiry timeline settles only the legs that have expired by each point in time. It reprices the rest. Both use the same pricing model as the market. Each option keeps its own implied volatility while the spot moves. This is called the sticky-strike convention. At zero shock, the line equals the book's current mark.
| Lowest implied volatility a shift can reach, percentage points | 0 |
|---|---|
| Risk-free rate / dividend yield used, percent a year | 7 / NIFTY 0.6 · BANKNIFTY 0.1 |
| Time presets, minutes | 30, 120 |
| Points drawn per scenario line | 61 |
| Spot shocks in a cross-index slice, percent | -10, -6, -4, -2, 0, 2, 4, 6, 10 |
Open-interest panel settings
The OI panel reads the published tape only. The concentration view shows the five largest strikes per side. The premium shown is that option's last traded price. The expiry-transfer view reports the tape's pattern over calls, puts and futures. It never says who traded. Settlement at expiry is reported apart, as a lifecycle change. The volume bands are display thresholds, not a forecast.
| Change windows offered, minutes | 1, 3, 5, 15 |
|---|---|
| History sample interval, seconds | 5 |
| History kept, minutes | 16 |
| An open-interest reading counts as old after, seconds | 30 |
| Flat threshold for the price/OI reading, percent | 0.1 |
| Strikes shown per side in the concentration view | 5 |
| Concentration movement below this is called steady, percentage points | 0.5 |
| Volume-context bands: mostly new positions above / mixed above / churn below | 0.6 / 0.25 |
PRICES
How prices move
Each market starts from a scenario. The spot of each index moves in a mood that can trend, stay in a range, squeeze, widen or jump. The two indices share part of their moves. Implied volatility moves on its own too, and it tends to rise when the spot falls. Over time, it drifts back toward its usual level. The time of day changes volatility, spreads and activity. A gap can appear at each open. If a price leaves the range the market can handle, the market pauses rather than show a wrong number.
Open interest moves with the same bookkeeping that Market X-Ray: Open Interest shows. A trade that opens two positions raises open interest. A transfer leaves it unchanged. A close lowers it. Your paper orders never change it.
PRICING
How a contract is priced and quoted
Every listed option is priced as a European option, which can only be exercised at expiry. It uses the same model as Market X-Ray: Premium. The model takes the spot, the implied volatility at that strike and expiry, and the time left to expiry. It also uses a fixed interest rate and dividend yield. Before prices are shown, three checks run. Call and put prices must agree, which is called put-call parity. Prices must rise or fall in the right order across strikes. The price curve across strikes must not bend the wrong way. A quote is built around that fair value, with a spread and several price levels. The bid is never above the ask.
FILLS
How an order is filled
A buy takes the asks and a sell takes the bids, one price level at a time. It stops when the order is done or the available quantity runs out. Used-up quantity comes back after a few updates. A basket can fill all at once or leg by leg. A limit on the net debit or credit is checked with its sign, per basket. A stop trigger is not a fill. It sends a market or limit order, which then fills like any other.
CHARGES
Which charges are applied, and which are assumed
Every fill pays the index options or futures charges in force on its trade date. It also pays a flat brokerage, which is an assumption. The table below lists them, and each row names its source. One charge is not in the table. It is the securities transaction tax on an option exercised at expiry. It uses an assumed rate, and every such line is marked assumed.
COLLATERAL
How collateral is estimated
Collateral uses the larger of two loss checks for each index. One checks spot shocks and IV changes. The other checks loss at expiry across the listed strikes, from the current mark. Uncovered short tails add a floor based on notional. Each index is checked separately. Pending orders reserve extra collateral, net debit and charges.
EXPIRY
What happens at expiry and at session close
Options settle at the expiry session close against the settlement level. Futures settle each session, with their basis reset at the close. The clock stops at session boundaries and at the end of the market. Press Play or Jump to continue.
SETTLEMENT
Index contracts are cash-settled: no shares, no delivery, no stock wheel
Every contract in Paper Trading is a NIFTY or BANKNIFTY index option or index future. An index contract settles in cash. At expiry, the difference between the strike and the settlement level is paid or received in rupees. No shares change hands. So the stock-market habits built on delivery do not exist here. A short index put that finishes in the money is not 'assigned' any stock. It pays the settlement difference. A stock wheel cannot be run on an index. A wheel means you sell a put, take delivery of the shares, then sell a covered call on them. The cash-secured index put template says so when you apply it.
STORAGE
Where your money and trades are saved
Your money and trades are saved in this browser, on this device. Each change is saved whole, so a failed save leaves nothing half-done. Clearing browser data deletes them, so save a backup first. A second tab of the same name opens read-only. When you import a backup, you choose one of three things. Leave what you have as it is, replace it, or add the backup as a separate copy. Importing never adds its cash to the cash you have. Anything saved by a newer version of Paper Trading opens read-only, so nothing changes by mistake. If saving fails, the session carries on unsaved and every screen says so.
After the offline copy finishes installing, reload this Paper Trading page while online, or open it in a new tab. The core Paper Trading pages are then cached for offline use in this browser. A new site version waits until older session tabs close, so it does not replace a running session. Your money and trades still stay in this browser. Export a backup before clearing site data.
Questions readers ask
Why is no return shown as a percentage per year?
A few hours or days cannot establish a yearly return. Read the result for the period you traded.
Is the option exercise tax a published rate?
Not on this site yet. The market uses an assumed rate and labels every such fee line as assumed. The rate is shown below with that warning.
Can I run a stock wheel or take delivery of shares?
No. Index options and futures are cash-settled. No shares are delivered, so there is nothing to be assigned, hold or write covered calls on. The cash-secured index put template applies. Its warning explains that the cash covers a settlement difference, not a purchase.