Build Your First Stock Screener from Scratch (Using Free Tools)

This article is for educational purposes only and does not constitute financial advice.

There are around 4,000 publicly traded stocks on US exchanges. You can't research all of them. Nobody can.

A stock screener is how you shrink that universe to a manageable list of candidates worth studying. Instead of randomly scrolling through tickers or following tips on social media, you start with a set of measurable criteria — and you let the filter do the first pass.

This guide isn't about clicking around in a pre-built app and pressing "screen." It's about understanding why you'd set each filter, what it's telling you about a business, and how to combine filters intelligently. Once you understand the logic, any tool — including free ones — becomes useful.

The Two Types of Stock Screens

Before we talk tools, understand what you're trying to do.

Quantitative screens filter by numbers: P/E below 15, dividend yield above 3%, debt-to-equity below 1.0. These are fast, scalable, and form the first layer.

Qualitative screens filter by business characteristics: Does the company have a competitive moat? Is management shareholder-friendly? Is the business model easy to understand? These can't be automated — they require judgment and research.

A stock screener handles the quantitative layer. Your brain handles the qualitative layer. The screener narrows 4,000 stocks to 15-30 candidates; you then read about those candidates and decide which ones deserve deeper work.

Most beginners skip the quantitative layer (random stock picking) or skip the qualitative layer (buying whatever the screener spits out). You want both.

Free Screener Tools Worth Knowing

Finviz.com

Finviz is the workhorse of free stock screening for retail investors. The free tier is comprehensive enough for most purposes.

What it screens on: P/E ratio, forward P/E, P/S, P/B, PEG, dividend yield, payout ratio, EPS growth, revenue growth, debt/equity, current ratio, return on equity, return on assets, insider ownership, institutional ownership, short float, market cap, sector, country of exchange, and more.

Limitations of the free tier: data is delayed 15-20 minutes (fine for research, not for active trading), and the export function requires a paid "Elite" subscription. You can work around the export limit by building your screen and manually reviewing the results.

Access: finviz.com/screener.ashx

Macrotrends.net

Macrotrends isn't a screener per se — it's a historical financial data tool. But it's extraordinarily useful for the step after your initial screen: reviewing the multi-year trend of a specific metric for a specific company.

Want to see 10 years of Apple's free cash flow? Five years of AT&T's gross margin? Macrotrends has it in clean chart form, free. This is where you verify whether the numbers on your screener reflect a durable trend or a single good year.

Access: macrotrends.net

SEC EDGAR

Discussed in our 10-K guide, EDGAR gives you direct access to the primary source documents: 10-K annual reports, 10-Q quarterly reports, proxy statements. This is where serious research happens — not screeners.

Access: sec.gov/edgar

Yahoo Finance

Yahoo Finance's screener is less powerful than Finviz but more accessible for beginners — cleaner UI, integrated news, and direct links to company profiles. Good starting point before you graduate to Finviz.

The screener is at finance.yahoo.com/screener. The "Equity Screener" option gives you filtering by sector, market cap, P/E, dividend yield, analyst rating, and a handful of others.

The Building Blocks: Which Metrics to Screen On and Why

Price-to-Earnings (P/E) Ratio

What it is: Stock price divided by earnings per share. A P/E of 15 means you're paying $15 for every $1 of earnings.

Why it matters: High P/E means investors are paying a premium for expected future growth. Low P/E might indicate undervaluation — or it might indicate a business in decline. Context matters.

Value investor benchmark: Benjamin Graham suggested looking for P/E below 15 for defensive value plays. A reasonable modern starting point is below the 5-year average P/E for the company's sector. For the S&P 500, the historical average P/E is roughly 15-16x; anything significantly below that for a quality business warrants a look.

Screen direction: Filter for trailing P/E below 20 to start. Adjust downward (below 15, below 12) as you want stricter value criteria.

Price-to-Book (P/B) Ratio

What it is: Stock price divided by book value per share (total assets minus total liabilities, divided by shares outstanding).

Why it matters: Book value is the accounting value of what shareholders own. Stocks trading below book value (P/B < 1) were Graham's original hunting ground — he called these "net-net" situations.

Caveat: Book value is less meaningful for intangible-heavy businesses (software, brands, platforms) where the most valuable assets don't appear on the balance sheet. It's most useful for financials, manufacturers, and asset-heavy businesses.

Screen direction: Filter for P/B below 1.5 for asset-intensive sectors; use conservatively or skip for tech/consumer brands.

Dividend Yield

What it is: Annual dividend per share divided by stock price, expressed as a percentage.

Why it matters: For income investors, it measures how much cash you're getting paid annually relative to your investment cost. But as covered in our dividend yield traps guide, extremely high yields (above 7-8% for most sectors) are often warning signs, not gifts.

Screen direction: For dividend-focused screens, target 2-5% yield in combination with a payout ratio below 75%. This identifies meaningful yield with reasonable safety.

Debt-to-Equity (D/E) Ratio

What it is: Total debt divided by shareholder equity. Measures financial leverage.

Why it matters: High debt amplifies both gains and losses. A highly leveraged company has less flexibility to handle downturns, pay dividends, or invest in growth. In a rising rate environment, debt service consumes more cash.

Screen direction: Filter for D/E below 1.0 for most sectors. Utilities and REITs structurally run higher leverage and should be evaluated differently. Banks have entirely different capital structure conventions.

Return on Equity (ROE)

What it is: Net income divided by shareholder equity. Measures how efficiently the company generates profit from shareholders' invested capital.

Why it matters: Warren Buffett has repeatedly emphasized ROE as a key quality metric. Consistently high ROE (above 15%) over many years is one of the strongest signals of a durable competitive advantage.

Caveat: ROE can be artificially inflated by high debt (which reduces equity) or by buybacks (same effect). Verify that the ROE is driven by genuine profitability, not financial engineering.

Screen direction: Filter for ROE above 12-15% over 3+ consecutive years.

Current Ratio

What it is: Current assets divided by current liabilities. Measures short-term liquidity.

Why it matters: A current ratio below 1.0 means the company's short-term obligations exceed its short-term assets — a potential liquidity risk. Above 2.0 is generally comfortable. Graham specifically required a current ratio of at least 2.0 for his most conservative defensive screens.

Screen direction: Filter for current ratio above 1.5 to start.

EPS Growth (Earnings Per Share Growth)

What it is: The percentage change in earnings per share year-over-year, or compounded over multiple years.

Why it matters: A business that consistently grows earnings over time will eventually be worth more. EPS growth that's consistent across multiple years (not just one outlier year) suggests a business with real forward momentum.

Screen direction: For growth screens, filter for positive 5-year EPS growth. For value screens, you might relax this — some temporarily depressed earnings create value opportunities.

Building a Basic Value Screen on Finviz

Here's a starter screen you can input directly on Finviz:

Criteria:

Market Cap: Mid ($2B-$10B) or Large ($10B+) — this excludes micro-caps where data quality is lower
P/E: Under 20
P/B: Under 2
Debt/Equity: Under 1
Current Ratio: Over 1.5
ROE: Over 10%
Country: USA (unless you want to include Canadian-listed stocks)

On Finviz, these translate to:

Market Cap: "Mid" or "Large" (or set Min value)
P/E: under 20
P/B: under 2
Debt/Equity: under 1
Current Ratio: over 1.5
ROE: over 10%

Starting with these six filters, you'll typically get a list of 20-80 stocks depending on market conditions. That's your research universe — not your buy list.

The Step After the Screen

This is what separates screener tinkerers from real investors.

Once you have your list of 20-80 candidates, you need to do the work:

Eliminate obvious problems: Read a one-paragraph description of what each company does. If you don't understand the business or it's in a sector you won't learn, skip it.
Check the multi-year trend: For each remaining candidate, go to Macrotrends and pull up 5-year charts of revenue, gross margin, and free cash flow. Is the trend going in the right direction?
Check the valuation: Is the stock cheap because the business is genuinely undervalued, or cheap because the business is deteriorating? A low P/E on a shrinking business is not value — it's a value trap.
Run the Graham Number: For the candidates that survive steps 1-3, check whether the stock price is below its calculated intrinsic value. Our Graham Number Calculator does this automatically from EPS and book value — two numbers you'll find in any 10-K or on Macrotrends.
Read the 10-K for the top 3-5 remaining candidates. Yes, the actual 10-K. This is where you distinguish a real opportunity from a data artifact.

A Few Mistakes to Avoid

Too many filters: Add 15 criteria and you'll get 0-3 results — usually data anomalies. Start with 4-6 and expand from there.

Screen output ≠ buy list: The screen identifies candidates. Research determines whether to buy.

Ignoring sector context: A P/E of 25 might be cheap for a software company and expensive for a utility. Set expectations per sector, not in absolute terms.

Optimizing for a specific outcome: If you keep adjusting filters until you get the stock you already wanted, you've built a confirmation bias machine.

The Real Competitive Advantage

Screening isn't the edge. The edge is doing the work that comes after the screen.

Most people stop at the screener result. They see a low P/E, check the chart, and buy or don't buy based on vibes. Very few take the time to read the 10-K, understand the business model, trace the free cash flow, and form a real opinion about intrinsic value.

That gap — between screener output and actual informed judgment — is where the returns hide. Stock screening just gives you the starting list.

What you do with it is the whole game.

Free tools referenced in this article: Finviz.com, Macrotrends.net, SEC EDGAR (sec.gov/edgar), and Yahoo Finance. All are publicly accessible with no registration required for basic use. Screener criteria discussed are derived from standard value investing frameworks, including Benjamin Graham's Security Analysis (1934) and The Intelligent Investor (1949).