Gap Up and Gap Down Stock Scanner for NSE
18 prebuilt scans · 7 buy-side and sell-side pairs · runs on live NSE candles
A gap is the distance between yesterday's close and today's open, and the first hour usually decides whether it holds or fills. The plain gap-up and gap-down scans list stocks that opened 2% to 15% away from the previous close. The others look at what happened next: a gap that reversed inside the first candle, a gap that was fully erased, or a pullback inside a gap above yesterday's high.
Gaps above 15% are left out because they are mostly corporate-action adjustments, and a smaller ex-date gap can still slip through, so check the news before trading any gap.
Gap scans
Gap Down, Green Candle with Lower Wick
Opened 1-15% below the previous close, was bought off the low (lower wick of at least 0.5%) and is trading as a green day candle near its high. Judged on the live daily candle (official open, running high / low, latest price) against the previous official close - the same answer on 5m, 15m, 1h and 1d, refreshed every few minutes; best read after 3:15 PM.
Gap Up, Red Candle with Upper Wick
Opened 1-15% above the previous close, rejected from the high (upper wick of at least 0.5%) and is trading as a red day candle near its low. Judged on the live daily candle (official open, running high / low, latest price) against the previous official close - the same answer on 5m, 15m, 1h and 1d, refreshed every few minutes; best read after 3:15 PM.
Gap Down Recovery: Closed Above Previous Close
Gapped down 1-15%, printed a lower wick of at least 0.5%, then recovered the whole gap to trade above yesterday's close - a fully reversed gap (green on the day, not just a green candle). Judged on the live daily candle (official open, running high / low, latest price) against the previous official close - the same answer on 5m, 15m, 1h and 1d, refreshed every few minutes; best read after 3:15 PM.
Gap Up Trap: Closed Below Previous Close
Gapped up 1-15%, printed an upper wick of at least 0.5%, then sold off through the whole gap to trade below yesterday's close - a fully reversed gap (red on the day, not just a red candle). Judged on the live daily candle (official open, running high / low, latest price) against the previous official close - the same answer on 5m, 15m, 1h and 1d, refreshed every few minutes; best read after 3:15 PM.
Opened Above Yesterday's High, Red Candle (Buy Side)
Buy-side watch-list: the stock opened ABOVE yesterday's high (a gap that clears the whole previous range) and its latest completed candle on the chosen interval (5m by default) is red - a pullback inside a strong gap-up. Rules: Daily Open > 1 day ago High, and latest candle Close < Open. Pair it with your own support level (VWAP, the gap zone, yesterday's high) before acting. Not back-tested for edge.
Opened Below Yesterday's Low, Green Candle (Sell Side)
Sell-side watch-list, the mirror of the buy-side scan: the stock opened BELOW yesterday's low (a gap that breaks the whole previous range) and its latest completed candle on the chosen interval (5m by default) is green - a bounce inside a strong gap-down. Rules: Daily Open < 1 day ago Low, and latest candle Close > Open. Pair it with your own resistance level (VWAP, the gap zone, yesterday's low) before acting. Not back-tested for edge.
First Candle Gap-Down Reversal
The first candle (09:15 bar of the chosen interval) opened 1-15% below the previous close, then closed green with a lower wick near its high - a gap-down bought inside the very first candle. Pick 5m, 15m or 1h to set the first-candle size; visible once that candle has closed.
First Candle Gap-Up Reversal
The first candle (09:15 bar of the chosen interval) opened 1-15% above the previous close, then closed red with an upper wick near its low - a gap-up rejected inside the very first candle. Pick 5m, 15m or 1h to set the first-candle size; visible once that candle has closed.
First Candle Gap-Down Recovery: Closed Above Previous Close
The first candle opened 1-15% below the previous close, printed a lower wick, and closed back ABOVE the previous day's close - the whole gap recovered inside one candle.
First Candle Gap-Up Trap: Closed Below Previous Close
The first candle opened 1-15% above the previous close, printed an upper wick, and closed back BELOW the previous day's close - the whole gap erased inside one candle.
Gap Up Stocks Today (2%+)
Stocks that opened 2% to 15% above the previous close, on liquid names (Rs 10 Cr+ traded). Reads the official daily open, so the list is the same on every interval and updates through the session.
Gap Down Stocks Today (2%+)
Stocks that opened 2% to 15% below the previous close, on liquid names (Rs 10 Cr+ traded). Reads the official daily open, so the list is the same on every interval and updates through the session.
Gap Up and Open = Low (Strong Open)
Opened 1% to 15% above the previous close, the open is also the day's low and price is trading above it. Buyers took control from the first trade. Liquid stocks only (Rs 5 Cr+).
Gap Down and Open = High (Weak Open)
Opened 1% to 15% below the previous close, the open is also the day's high and price is trading below it. Sellers took control from the first trade. Liquid stocks only (Rs 5 Cr+).
Gap Down Reversal
Gap-down stocks that recover and close near the top of the candle.
First Candle Gap-Down Fade: Red Candle with Upper Wick
The first candle (09:15 bar of the chosen interval) opened 1-15% BELOW the previous close, spiked up (upper wick of at least 0.3%) and was sold back down to close red in the lower 40% of its range - a gap-down where the bounce was rejected and sellers kept control. Pick 5m, 15m or 1h to set the first-candle size; visible once that candle has closed.
How traders use these scans
- Read the first 15 to 30 minutes: holding the opening range suggests the gap is accepted, and filling it suggests a fade.
- Use the traps and reversals scans to find gaps that already failed.
- Pair a gap with a volume or VWAP rule to keep only the gaps that are holding.
Scans list setups that match fixed rules. They are not recommendations and none is back-tested for an edge.
Frequently asked questions
Which open price do the gap scans use?
The official daily open against the previous official close, so the list is the same on the 5m, 15m, 1h and 1d intervals. The first-candle scans use the first bar of the interval you pick.
Does a gap up always continue?
No. Some gaps hold and extend and others fill. The scans only list the setups; none is back-tested for an edge.
Why is there a 15% cap?
Moves beyond 15% at the open are mostly splits, bonus issues and similar adjustments rather than a real opening move.