Float data is only as good as its last update. For large companies that rarely matters. For small caps, which can issue millions of new shares between quarterly reports, it can be the difference between a micro-float setup and a stock with plenty of supply. Every provider below is good at something. The question is which one keeps up when a small cap's share count changes.
Published by Ask Edgar, one of the providers on this list. Details about other providers are from their public sites and our own checks in October and November 2026.
Quick picks
- Most up-to-date small-cap float, with the full history and an API: Ask Edgar
- A simple dilution app with float data, including on a free plan: DilutionTracker
- Free, quick lookups across the whole market: Yahoo Finance
- Fast screening across thousands of stocks: Finviz
- The original source, if you have the time: SEC filings
Why float data goes stale
Three numbers get called "float", and they're not the same:
- Shares outstanding: every share the company has issued.
- Float: the shares held by people other than insiders and affiliates.
- Tradable float: the float minus restricted shares and shares under lockup, the part that can actually trade today.
Most data providers refresh these from quarterly and annual reports. Small caps can issue millions of shares in between, through ATM sales, warrant exercises, conversions and private placements. The updates often appear in places generic feeds skip: an exhibit attached to an 8-K, or a prospectus supplement filed late in the day.
That matters twice over. A stale float changes which stocks make your screen and how you size a trade. It also hides dilution risk, because under the baby shelf rule, how much a small company can sell from its shelf depends on its float.
A real example: XXII in October 2026
- Early October: screeners showed 22nd Century Group (XXII) as a micro float of roughly 700,000 shares.
- 22 October: an exhibit attached to the company's 8-K put shares outstanding at 3,416,441.
- 23 October: XXII ran premarket, then faded hard. That evening, a prospectus supplement and the company's disclosure showed it had sold 15.8 million shares through its ATM during October, raising about $4.7 million. Shares outstanding had reached about 19.2 million.
- Late October: when we checked, Yahoo Finance still listed about 700,000 shares outstanding and Finviz showed a float of about 600,000. Yahoo was still showing the same figure on 3 November.
Anyone trading XXII as a 700,000-share micro float missed that the company was selling stock into the move. At 3.4 million shares, the baby shelf rule gave it room to raise roughly $4 million, and it used it.
It also fed on itself. The baby shelf limit is one-third of the float's value at the highest closing price in the last 60 days, minus whatever the company sold in the past 12 months. Selling shares grew XXII's float, and even after subtracting October's sales, that left room to sell more. The company followed with a new prospectus supplement for an ATM of up to $18 million.
Watch the full walkthrough, with the filings and the shelf math: XXII float walkthrough on YouTube.
The providers
To be fair to the big providers, almost nobody watches these companies closely. The people trading them are the exception, and that's who this list is for.
Ask Edgar
- Best for: small-cap traders and developers who need the float as of the latest filing, not the latest quarter.
- What it does: tracks share counts reported across SEC filings, including exhibits and filings between quarterly reports, along with changes from reverse splits and share issuances. Each update is kept as a dated checkpoint with its source document, and float, tradable float and shares outstanding are labelled separately. The same data is in the Ask Edgar app and the API.
- Where it falls short: it's built for small caps, so it isn't the place for broad market screening or large-cap fundamentals, and there's no free trial right now.
DilutionTracker
- Best for: newer traders who want a simple dilution app with good float data, including on a free plan.
- What it does: its pricing page lists audited float alongside live shelf data, a dilution risk rating, institutional ownership and short interest, with float included on its free Casual plan.
- Where it falls short: if you want float data in your own tools, its pricing page FAQ says API access comes "with an institutional subscription".
Yahoo Finance
- Best for: free, quick lookups across the whole market, with prices, charts and financials in one place.
- Where it falls short: share counts can lag on small caps. In late October, and still on 3 November, it showed XXII at about 700,000 shares outstanding, after filings had shown 3.4 million and then 19.2 million.
Finviz
- Best for: fast screening across thousands of stocks with a wide range of filters.
- Where it falls short: a screen is only as good as its inputs. In late October it showed XXII's float at about 600,000 shares.
SEC filings
- Best for: anyone who wants the original source, free.
- Where it falls short: the numbers are spread across 10-Q and 10-K cover pages, 8-K exhibits and prospectus supplements, so keeping up by hand takes real time on an active small cap.
How to check a float before you trust it
Whatever source you use, ask three questions before you build a trade around a float number:
- When was the share count last updated? A float from the last 10-Q can be months old.
- Have later filings changed it? Check recent 8-K exhibits and prospectus supplements, especially after a big move.
- How much stock can the company still sell? A small float with room left on a shelf or ATM can grow fast. Our guide "What Is an At-the-Market (ATM) Offering? A Trader's Guide" explains how.
Get float data from the API
The historical float endpoint returns a company's share structure as a series of checkpoints, each with the filing it came from. Request it with your API key in the API-KEY header; the quickstart shows how. The fields that matter here:
- float, tradable_float and outstanding_shares: the three share counts, labelled separately.
- reported_date and filed_at: when the share count applies, and when the filing became public.
- document_url and outstanding_shares_description: the source filing, and a note on how the count was determined.
- restricted_shares and affiliate_shares: what's held back from the float.
Set latest_data to true for just the current figures, or leave it off to get the full history. For backtests, use the latest checkpoint with a reported date before your event date, so you're using the share count traders had at the time.
Common questions
Why does float differ between sites? Each provider updates on its own schedule and from its own sources. Some only refresh from quarterly reports, so a recent issuance won't show up until the next one.
What's the difference between float and shares outstanding? Shares outstanding counts every share. Float leaves out shares held by insiders and affiliates, which is closer to what can actually trade.
How fast can a small cap's float change? Very fast. XXII went from about 3.4 million shares outstanding to about 19.2 million within days, through its ATM.
Start building
Check any small cap's float in the Ask Edgar app, or pull the full history into your own screener with the Ask Edgar API.
Last checked against the Ask Edgar API docs and DilutionTracker's pricing page on 3 November 2026. Yahoo Finance and Finviz figures are from our checks in late October 2026; Yahoo was checked again on 3 November.