Skip to main content
Tools and Platforms

Scanner Tools for Setup Detection

Pomegra Learn

What Are Stock Scanner Tools and How Do You Use Them to Find Trade Setups?

A stock scanner is software that automatically filters thousands of stocks against criteria you define to identify potential trade setups. Instead of watching 3,000+ stocks on the NYSE and NASDAQ manually, a scanner runs your rules in real time and alerts you when a stock matches. For active traders, a scanner is essential because it eliminates the need to look at every stock; instead, the scanner brings opportunities to you. The quality of your scanner directly impacts the quality of setups you find. A poorly configured scanner drowns you in false signals; a well-tuned scanner finds real opportunities with high win rates. This article explains how scanners work, compares the major platforms, and shows you how to build scanners that match your edge.

Quick definition: A stock scanner is a program that filters a universe of securities (e.g., all stocks on the NYSE, all US options) against pre-defined technical or fundamental criteria (e.g., "moving average crossover," "gap up 3% on volume," "price above support") and alerts you when conditions are met.

Key takeaways​

  • Scanners save time by eliminating manual stock watching — You define rules once; the scanner checks thousands of stocks against those rules automatically.
  • Scanner quality depends on your setup rules — A scanner is only as good as the criteria you program into it. Vague rules (e.g., "strong uptrend") produce weak signals; specific rules (e.g., "close above 20-day high on 120% average volume") produce better results.
  • Real-time scanning requires a broker or paid scanner — Free or delayed scanners (15–20 minute lag) miss real-time setups. Choose a broker-bundled scanner or pay for real-time.
  • Multiple timeframes require multiple scanners — A 1-minute breakout scanner and a 5-minute momentum scanner are different configurations; you may need multiple scanner instances.
  • Backtesting scanner rules improves accuracy — Before deploying a scanner, test the rules on historical data to see how many false signals it generates versus real opportunities.

How Scanners Filter Stocks: The Basic Mechanics​

A scanner works in three steps: (1) Define criteria (moving average crossover, volume spike, gap, price at support); (2) The scanner applies those criteria to all stocks in its universe (e.g., all 3,000 US equities) in real time; (3) When a stock matches all criteria, it alerts you.

Here's a simple example. A breakout scanner might have these rules:

  • Price closes above the 20-day high
  • Volume on the close is >120% of the average volume
  • Price is above the 50-day moving average
  • Stock price is between $2 and $20

A stock universe of 3,000 stocks is scanned every minute (or every 5 minutes, depending on the scanner's frequency). When ACME closes above its 20-day high on 150% volume and the price is above the 50-day MA, ACME appears in your scanner results. You then chart ACME, confirm the setup visually, and decide whether to trade.

The more specific your criteria, the fewer false signals you'll get. A scanner with only one rule (e.g., "price above 50-day MA") will generate hundreds of results daily, most of which are not tradeable. A scanner with five well-chosen rules might generate 3–10 results daily, a much more manageable number.

Technical vs. Fundamental Scanners​

Technical scanners filter based on price action: moving average crosses, support/resistance breaks, volume spikes, Bollinger Band breaks, RSI extremes, etc. Most active traders use technical scanners because they operate in real time and align with short-term trading timeframes.

Fundamental scanners filter based on financial metrics: earnings growth, P/E ratios, dividend yields, debt levels, etc. These are used by swing traders and investors looking for longer-term opportunities. Fundamental data updates quarterly or daily, so fundamental scanners are slower than technical scanners.

For day traders and 1–5 minute scalpers, technical scanners are the only option. For swing traders holding positions overnight to weeks, you might use both: a technical scanner to find daily breakouts, then a fundamental scanner to avoid earnings risk or dividend ex-dates.

Common Scanner Criteria and What They Signal​

Gap up on volume — Stock opens 3%+ higher on 200%+ average volume. Often indicates institutional buying or positive news overnight. Popular for breakout trades.

Support bounce — Price falls to a previous support level, then bounces upward. Signals mean-reversion or the beginning of an uptrend. Frequently used for short-term reversal trades.

Moving average crossover — Fast moving average (e.g., 10-period) crosses above a slower moving average (e.g., 50-period). Signals momentum shift. Can generate many false signals on choppy stocks.

Volume breakout — Price breaks above a previous resistance level on volume significantly higher than average. Signals institutional interest and breakout potential. One of the most reliable setups.

RSI divergence — Price makes a new high, but RSI (relative strength index) does not. Signals potential exhaustion. More advanced traders use divergences; beginners should avoid until they understand indicator limitations.

Bollinger Band squeeze and break — Price compresses into a narrow range (low volatility), then breaks out of a Bollinger Band. Signals an expansion move coming. Popular for swing traders.

Earnings setup — Stock is approaching earnings, with price near support or above a key trendline. Earnings can trigger large moves; some traders trade into earnings, others avoid it.

Major Scanner Platforms for Active Traders​

Finviz Elite — A popular screener with real-time technical and fundamental filters. Costs $40/month; includes alerts via email. Good for beginners because the interface is intuitive and pre-built scanners are included.

Trade Ideas — An AI-powered scanner using machine learning to identify patterns. Costs $99–$300/month depending on features. Popular among day traders for its advanced pattern recognition. Includes alerts and backtesting.

Thinkorswim (TD Ameritrade) — Includes a powerful built-in scanner called "ThinkorSwim Watchlist" with real-time criteria. Free with a TD account ($2,000 minimum deposit). The scanner is less user-friendly than Finviz but includes backtesting and is integrated with the charting platform.

Finviz (free tier) — Free version of Finviz with delayed data (15–20 minute lag) and limited filters. Useful for learning but too slow for day trading.

Interactive Brokers Trader Workstation — Includes a scanner called the "Monitor" feature with pre-built and custom scans. Free with an Interactive Brokers account. Powerful but requires technical knowledge to set up.

Webull Scanner — Free real-time scanner included with Webull brokerage. Limited compared to paid platforms but cost-effective for beginners.

StockToTrade — Designed specifically for day traders. Includes pattern recognition (gap and go, VWAP bounces, etc.) and alerts. Costs $99/month standalone or $199/month with day trading chat room access. Very popular with breakout traders.

Decision tree​

Real-world Examples​

Scenario 1: 1-minute gap-and-go scanner

  • Rules:
    • Stock gapped up 3%+ on 200%+ volume
    • Price is above VWAP (volume-weighted average price)
    • Relative volume is >150%
    • Only stocks in the $3–$20 price range
  • At 9:35 AM, the scanner finds XYZ stock, which gapped up 4.2% on 250% volume
  • You chart XYZ, see it's consolidating above VWAP
  • Place a limit buy at the high of the consolidation bar
  • Entry fills; you set a stop below the gap low and a target 1.5× the gap size
  • Outcome: The scanner found the setup in seconds; manual scanning would have missed it

Scenario 2: 5-minute support bounce scanner

  • Rules:
    • Price touches a support level (previous day's low or previous week's low)
    • RSI is below 40 (oversold)
    • Volume on the bounce bar is above average
    • Price closes above the support level
  • At 2:15 PM, the scanner alerts that ABC stock has bounced off support on elevated volume
  • You confirm on a chart; the support is a clear level from last Tuesday
  • Place a limit buy at the consolidation high
  • Stop below support; target at previous resistance
  • Outcome: The scanner caught the bounce early; you avoided watching passively all day

Scenario 3: Swing trader earnings scanner

  • Rules:
    • Earnings are within 7 days
    • Price is within 1% of a 50-day high
    • Volume has been rising over the last 3 days
    • Stock is in a breakout mode (closes above 20-day high at least 2 of the last 3 days)
  • The scanner identifies 5 candidates
  • You chart each, manually check for support levels and trendlines
  • Place alerts on two of the five stocks for breakout entries above key resistance
  • One triggers a day before earnings; you exit with profits before the event
  • Outcome: The scanner filtered thousands of stocks down to 5 high-probability earnings plays

Common Mistakes​

Building scanners with too many criteria. Each additional criterion reduces results. A scanner with 10 rules might find only 1 stock per day—perhaps too restrictive. Start with 3–5 rules and test before adding more.

Not backtesting scanner results. Some traders build a scanner, run it live, and then complain it generates false signals. Before deploying, backtest the criteria on 6–12 months of historical data. A setup that worked 20% of the time in backtesting is a weak setup.

Using delayed data in a real-time scanner. A scanner with 15-minute-delayed data is useless for day trading. Ensure your scanner uses real-time data; some brokers offer delayed scanners as a free bonus (Finviz free tier).

Ignoring the "why" in scanner results. Some traders treat the scanner like a magic box: if the scanner alerts, they trade. Instead, always chart the result and understand why the setup is there. A scanner might alert to a price crossing a moving average, but on the chart, you see it's at a major resistance where price has repeatedly failed.

Over-optimization of scanner rules. Tuning scanner criteria based on last week's winning trades creates a curve-fit scanner that won't work in the future. Build rules based on repeatable patterns, not on optimizing for your winners.

FAQ​

How often should my scanner run?​

For day traders: Every 1–5 minutes. For swing traders: Every 1 hour or at the end-of-day (4 PM ET). For position traders: Once daily. Match the scanner frequency to your timeframe.

Can I build my own scanner?​

If you're technical, some platforms (Trade Ideas, StockToTrade, some brokers) allow custom rule-building. Most retail traders use pre-built scanners or slightly modified versions. Building a scanner from scratch requires programming knowledge.

What's the difference between a scanner and a screener?​

The terms are often used interchangeably. Technically, a "screener" filters a static list (e.g., all stocks as of 4 PM), while a "scanner" runs continuously in real time. For practical purposes, they're the same tool.

Should I trust AI-powered scanners like Trade Ideas?​

AI scanners can identify complex patterns humans miss. However, they're black boxes; you don't always understand why they alert. Use them as a supplement to rule-based scanners, not as a replacement. Backtest thoroughly before trusting.

How many scanner alerts should I expect daily?​

If you're a day trader running a breakout scanner, expect 3–15 alerts daily. If you get 50+, your criteria are too loose. If you get 0–1, criteria are too tight. Aim for the sweet spot where you can manually chart and confirm 5–10 ideas per day.

Can I scan for options setups?​

Yes. Some platforms (Trade Ideas, StockToTrade) allow options scanning (e.g., "call volume spiking," "IV at 52-week low," "short call IV rank below 30%"). Most brokers' scanners are stock-only.

Summary​

Stock scanners are essential for active traders because they automatically filter thousands of stocks against your criteria and present only the ones matching your setup. Real-time scanners are mandatory for day trading; delayed scanners are too slow. Broker-bundled scanners (thinkorswim, Trader Workstation, Webull) are cost-effective for beginners; paid platforms like Trade Ideas and StockToTrade offer advanced pattern recognition. The key to scanner success is building rules that match your repeatable edge: gap-and-go traders need gap rules, support bounce traders need support detection, breakout traders need volume confirmation. Always backtest scanner rules on 6–12 months of historical data before deploying live; manually chart every alert to ensure you understand the setup context. Combine your scanner with charting software, a Level 2 order book, and alerts, and you'll have a complete toolkit for finding and executing high-probability trades.

Next​

Alert and Notification Systems