What a Stock Screener Does (and What It Doesn't)
A screener checks every listed stock against your rules and returns only the names that pass all of them. Typical rules include market cap, price, volume, P/E ratio, RSI and moving averages.
It does not read filings, judge management or say when to buy. It answers one question: which stocks match these numbers right now.
- Finviz's free tier includes the full stock screener, heat maps and news at no cost.
- Finviz free quotes are delayed about 15 minutes for Nasdaq and 20 minutes for NYSE and Amex.
- Finviz free users get preset ranges only, not custom numeric ranges.
- TradingView's free screener covers about 14,000 stocks and 4,100 ETFs; exports and real-time streaming need a paid plan.
- The official Finviz iPhone app is listed on the App Store, though some 2026 reviews still say no mobile app exists.
The Filters That Matter Most: Valuation, Growth, and Momentum
Most screens combine five filter groups: valuation, growth, momentum, size and liquidity, and dividends. Start with three to five filters so the output stays manageable.
Valuation filters pick stocks the market has marked down, while momentum filters pick stocks it is already rewarding. Combining them forces a choice between those two bets.
- Valuation: P/E, PEG and price-to-sales.
- Growth: EPS growth. Yahoo's 'Undervalued Growth Stocks' preset requires earnings growth above 25% with relatively low P/E and PEG.
- Momentum: price change, RSI and distance from moving averages.
- Size and liquidity: market cap and volume, which set how easily a position can be traded.
- Dividends: yield, the income side of the screen.
How to Build a Screen Step by Step
Build the screen one rule at a time and check the match count after each addition. If one filter returns 2 stocks or 2,000, adjust its threshold before adding the next rule.
Finviz's free tier lets you save 50 screener presets, so you can keep each version for comparison.
- Step 1: Set the universe, for example US-listed stocks with market cap above $10 billion (illustrative threshold).
- Step 2: Add one valuation rule, such as P/E below the sector median or PEG under 1.5 (illustrative).
- Step 3: Add one growth rule, such as EPS growth above 10% over the last year (illustrative).
- Step 4: Add one momentum check, such as price above the 200-day moving average.
- Step 5: Sort results by market cap or a valuation column and review only the top 20.
Why Screen Results Are a Starting List, Not a Buy List
A screen returns stocks that met your rules on the day you ran it, not stocks that are mispriced or likely to rise. Each result needs checks the screen cannot make, starting with debt, cash flow and earnings quality.
Fintwit's data shows how the same list can split into very different cases. Apple sits at a 64 AI investment score with bearish sentiment, while Microsoft, Coca-Cola and Johnson & Johnson score 83 and read bullish.
- Apple (AAPL): $342.37 price, median analyst target $315.0, about 8% below the price; 0.4% of tracked X investors bought in 30 days, 0.0% sold.
- Microsoft (MSFT): $530.61 price, median target $600.0, implying about 13% upside; 30-day performance of -0.8%.
- Coca-Cola (KO): $95.67 price, median target $97.5, implying about 2% upside; 30-day performance of +8.7%.
- Johnson & Johnson (JNJ): $276.22 price, median target $300.0, implying about 9% upside; 30-day performance of +5.7%.
- Checklist: confirm whether P/E uses trailing or forward earnings, check debt against cash flow, and read the last two quarters for one-time gains.
Common Screener Mistakes to Avoid
A low P/E can flag a business in decline as easily as a bargain, so a valuation hit needs a fundamentals check. Yahoo's 'Undervalued Growth Stocks' list is rule-based and will surface names that meet its thresholds whether or not they are mispriced.
Verify each number on the source's own page before comparing tools, because sources disagree on basic facts.
- Treating a screen result as a buy signal.
- Stacking more than five filters, which often returns zero names and hides the trade-off.
- Using 15-to-20-minute delayed free quotes for premarket momentum scans.
- Assuming counts match: one 2026 guide cites 60+ Finviz criteria, another cites 70+.
- Overlooking update timing when comparing free screeners.
Frequently asked questions
- Is a stock screener free to use? Usually yes for basic use: Finviz's free tier, Yahoo Finance's screener and TradingView's Basic plan all include screening, while real-time data and exports typically require paid plans.
- What is the best stock screener for beginners? Sources disagree: one 2026 test ranks Yahoo Finance easiest, while others rank Finviz first for simple US filtering and TradingView first for charts. Test two free tools and keep the one that fits your workflow.
- What filters should I use in a stock screener? Start with three to five filters across valuation (P/E, PEG), growth (EPS growth), momentum (RSI, moving averages) and size (market cap or volume).
- Can a stock screener find undervalued stocks? It can find stocks that pass cheapness rules such as a low P/E or PEG, but it cannot confirm that a stock is undervalued, so each result still needs fundamental research.