AI Gap Analyzer: Manual Trade Review

This AI trade analyzer reviews a gap-related setup, a proposed trade plan, that you enter manually. It does not scan opening gaps or calculate measured gap-fill odds. Quick mode checks your entered prices and quantity; Detailed mode adds context and your reasoning. Use the response to question assumptions in your plan. AI feedback and displayed scores can be wrong.

Measure the opening gap before interpreting it

For this page, opening gap means the difference between the current session’s opening price and the previous session’s close. State both prices, the date and the instrument when recording it. A gap above the prior close and a gap above the entire prior trading range are different observations.

The size of the opening gap does not establish the direction of the next move. A gap fill means a later return to the reference level you defined. Record which level and time window you mean before looking at the later outcome. The gap analysis calculator covers a separate numerical comparison.

Fidelity’s chart-pattern teaching material describes gaps as prices without trading and warns against accepting market lore without evidence. That supports checking the observations; it does not establish a universal fill rate for an index or stock.

The four common types of gaps

Chart teachers usually sort gaps into four types. The labels are applied after the fact, so a gap often cannot be named at the moment it appears. StockCharts' chart school describes them this way.

A gap is filled when price retraces at least to the close of the day before the gap. The same page cautions that the idea that all gaps get filled might not hold, especially for breakaway and runaway gaps. That is why this page asks you to name the reference level and the time window before you look at the result.

The controls you will actually see

There is no separate gap database or probability model here. To include an opening scenario, put the relevant facts into Detailed mode’s reasoning. Quick mode does not provide a free-text gap description field.

Choose units carefully. With Stock/Equity, Qty is the number of shares. Index selections use the tool’s contract multiplier. Confirm the actual contract quantity independently. Never mix an underlying-index level with option premiums when entering entry, stop and target.

Worked example: gap size and trade risk answer different questions

This invented cash-share scenario uses a previous close of ₹100 and an opening price of ₹102. Opening gap = 102 − 100 = ₹2, or (102 − 100) ÷ 100 × 100 = 2%. These prices describe an unnamed stock and are not market data.

Separately assume a proposed long trade entered at ₹102, with Stop Loss ₹100, Target ₹106, Qty 10 shares and Capital ₹50,000. Choose Stock/Equity. The target and stop are illustrative inputs for checking arithmetic, not recommended levels.

• Price distance to the stop: 102 − 100 = ₹2 per share.
• Planned cash risk: ₹2 × 10 = ₹20.
• Price distance to target: 106 − 102 = ₹4 per share. Planned reward: ₹4 × 10 = ₹40.
• Reward per risk: 40 ÷ 20 = 2, displayed as a risk-to-reward relationship.
• Account risk: 20 ÷ 50,000 × 100 = 0.04%.

Quick Risk % uses the account-risk calculation, but its card rounds to a single decimal place: this example displays 0.0% even though the planned risk is positive. Detailed mode also has a price-distance risk percentage: 2 ÷ 102 × 100 = 1.96%, rounded. That is a different denominator. A percentage of entry price and a percentage of account capital should not be compared as if they mean the same thing.

In this example the opening gap and planned stop distance happen to match. They need not match in another setup. A later entry changes the trade calculation even though the opening gap for the session stays unchanged.

Give the AI observations it can challenge

• Name the instrument and state whether the entered prices are share prices, futures prices or option premiums.
• Record the previous close and opening price from a consistent source.
• Describe what was actually visible when you formed the plan, including the observation time.
• Separate a confirmed public event from a possible explanation for the gap.
• State your own entry, the price where your trade idea fails, and your loss budget. Identify information you have not verified.

A useful reasoning note might say that the open was above the previous close, but the rest of the session was still unknown. It should not say that the gap will fill merely because other gaps have filled before. The gap-up and gap-down guide explains the terms further.

Reading pre-open cues for a Nifty gap

Traders look at several things before the opening bell. None of them can tell you where Nifty will open, and each has gaps in what it shows.

• GIFT Nifty. NSE says GIFT Nifty contracts are accessible for almost 21 hours a day, so they trade while Indian cash markets are shut. The price shows what traders on that venue are paying, and the NSE open can still differ.
• Global markets. The US close and early Asian trading happen before the Indian open. See the global market hours mapper for the times, and note that seasonal clock changes shift them.
• Overnight news. Company results, policy announcements and global events can move prices while the exchange is closed. Record what was public and when, as the section above suggests.
• The pre-open session. NSE runs a pre-open call auction before the normal session. Our pre-open guide explains it.

A note in your journal might read "GIFT Nifty was above the previous Nifty close at 8:45; no view on whether it holds". It records the cue and avoids claiming a result. The separate GIFT Nifty gap calculator does the arithmetic for a gap if you want it.

Gap fill versus gap and go

Two plans are widely discussed. A gap fill plan expects price to move back toward the previous close. A gap and go plan expects price to carry on in the direction of the gap. Neither is right by default, and which one fits depends on the type of gap, which is hard to know early.

• Define the reference. For a fill plan, write the level (usually the previous close) and the time window you will wait.
• Define the failure point. For both plans, write the price at which the idea is wrong before you enter.
• Record the first-hour range. StockCharts' gap strategies page uses the range of the first hour as a reference for entries and stops. In India you can compare it with your own opening-range notes; see how to trade the opening range.
• Log it either way. The same page advises logging entries and exits and subtracting commissions and slippage, which is what a journal is for.

Our guides on trading gap up and gap down, the gap fill strategy and the gap up short strategy describe the setups. They teach the idea. They do not tell you what will happen next.

Review the answer without treating it as a forecast

Check whether the response has used your instrument, prices and units correctly. If it adds a news event, historical statistic or market level that you did not supply, verify it before relying on the explanation. A plausible account of why a gap occurred can still be invented.

The Detailed scorecard includes estimated probabilities and expected-value style figures built from assumptions, rather than a tested sample of comparable gaps. Expected value means an average outcome under assumed probabilities. A score or confidence percentage does not establish the chance that this gap fills or your trade wins.

The response can also use directional verdict wording. Treat that wording as unverified model output; it does not establish a signal or an order instruction. The tool does not place trades.

Allow for prices your planned stop cannot capture

The arithmetic uses the stop you typed. It does not model the actual price available after a gap or a fast move. Fidelity’s risk notice states that a stop trigger does not assure the execution price. A larger realised loss can therefore coexist with a correctly calculated planned risk.

The form does not deduct trading charges in the simple risk and reward distances. Check cash loss after costs separately. The risk/reward calculator provides another way to inspect assumed distances, and the opening-range guide addresses a different observation from the opening gap.

Setting a stop on a gap day

On a gap day the first price is not the previous close. If your plan has a stop below the previous close and the stock opens below it, the stop can be triggered at the open or filled at a worse price than you typed. The planned risk on the card is a distance you typed, not the loss you will certainly take.

• Write a stop that is based on a level in your plan, such as the day's opening range, not on a number that happens to fit your budget.
• Reduce the quantity if the distance from entry to stop is large on a gap day. The Capital and Qty fields show how the cash risk changes.
• Compare the planned loss with the actual loss after the trade. A gap between the two is a lesson about execution, not about the analyzer.

A sample note to give the AI review

Detailed mode accepts free text in Your Trade Reasoning. A useful note states facts, then the plan, then the doubts. Made-up example: "Previous close and opening price taken from my terminal at 9:16. Open above previous close. Plan: wait for the first fifteen minutes, enter only on a break of that range, stop below the range low. Doubts: no news seen, volume unknown." The AI can then question the plan. It cannot confirm the prices.

Gap analysis questions

Sources

• Fidelity: gaps, pattern limits and stop execution, checked 16 Oct 2026.