Catch the small-caps gapping up — before the open
The classic low-float momentum screen: cheap stocks gapping up hard in the premarket or after-hours, on high relative volume, with a real news catalyst. Below is exactly how it works — every filter, every threshold, and the plain math behind each number. Nothing hidden.
Five things line up at once
A name only makes the board when all five are true at the same time. These are the scanner's default thresholds — the ones the free preview runs on.
Gapping up
The stock is up hard versus the session's reference close — premarket vs yesterday's close, after-hours vs today's close. That extended-hours move is the fuel a momentum play needs.
gap≥ 10%Low float
Few shares available to trade, so incoming demand moves the price faster. Low float is what turns a catalyst into a violent move.
float≤ 10M sharesHigh relative volume
Trading far more than it normally does for this time of the morning — the tell that real, unusual interest is showing up early.
premkt vol≥ 50kCheap price
In the low-dollar range where small-cap momentum runs happen and a small account can take a real position.
price$1 – $20Has a catalyst
A real news headline in the last 24 hours — earnings, an offering, an FDA or contract event — the reason the stock is moving at all.
news≤ 24hNo black box — here's the math
Every column on the scanner is a plain, public calculation. We show them all. If we're this open about the free screener, you know the paid tools are built the same honest way.
Gap %
(session price − reference close)
÷ reference close × 100The true gap versus the session's reference close — yesterday's close for premarket, today's close for after-hours — not the open-to-open gap, so an extending runner reads correctly.
Relative volume (RVOL)
premarket volume
÷ 10-day avg volume
for this time of dayTime-of-day normalized, so 8:30am volume is compared to a typical 8:30am — not to a whole day. That's what makes an early spike stand out.
Float
shares available
to trade publiclyFree-float shares outstanding. Smaller float means each buy order moves the price more — the amplifier on any catalyst.
ATR (14)
14-period average
true rangeHow much the stock typically moves in a bar — a plain read on how volatile it is, straight off the daily chart.
RSI (14)
14-period relative
strength indexThe classic momentum oscillator (0–100). Context on whether the move is already stretched or just getting going.
Has news
any headline in the
last 24h (Benzinga)A real, sourced catalyst check on the exact ticker — so a mystery mover without a reason is easy to tell apart from a real story.
Run the top 10 free — no login, no key
The scanner is live as a free, keyless MCP endpoint. Point Claude Desktop, Cursor, or any MCP client at it and just ask “what's gapping?” — it auto-picks the live session and returns the top 10 on the default filters. Premarket 4:00–9:30am ET, after-hours 4:00–8:00pm ET.
{
"mcpServers": {
"traderdaddy-free": {
"type": "http",
"url": "https://api.traderdaddy.pro/api/mcp/free"
}
}
}On the Claude iOS / Android / web app? The mobile Connectors UI can't take a config file — add this URL instead (Settings → Connectors → Add custom connector), tap Connect free, and you're in. No key, no login:
https://api.traderdaddy.pro/api/mcp/free/connectA key unlocks the whole board
The free preview is the same engine, capped. A TraderDaddy Pro API key opens it all up — and hands you the rest of the toolkit.
Tune every filter
Set your own float, price, gap %, and volume floors — dial the screen to your exact playbook instead of the defaults.
Up to 50 results
See the full ranked board, not just the top 10 preview.
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