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Market Research on a Census, Not a Sample

"How many e-commerce companies run Shopify in Germany?" should be a query, not a six-week consulting engagement. We classify 102 million domains into industry verticals and keep the classifications current — so strategy teams, analysts and PE/VC researchers can size markets, map competitors and detect category shifts from observed data instead of extrapolated panels.

102M
classified domains, queryable by vertical
12+
prebuilt slices: tech, traffic, funding, hiring
IAB
standard taxonomy plus expanded verticals
Live
re-classification tracks market shifts over time
Try the Live Demo Request a Sample API Documentation

The problem: TAM slides built on stale panels and gut feel

Most market-sizing work still starts from analyst reports written a year ago, company registries that lag reality by quarters, and survey panels of a few hundred firms extrapolated to whole economies. The result is a number nobody can interrogate: you cannot list the companies behind it, segment it by technology or geography, or re-run it next quarter to see movement.

Registries lag the market

Company registers record what a firm filed as, not what it does today. Fast-moving categories — AI tooling, quick commerce — are invisible until the codes catch up.

Panels miss the long tail

Survey-based sizing over-represents large, reachable firms. The long tail of small companies — often the actual target market — never answers the survey.

A number without a list

"~48,000 companies" is not actionable if you cannot enumerate, sample and verify them. Diligence teams need the underlying domains, not just the headline count.

Trends surface too late

By the time a category shift appears in published research, it is priced in. Detecting it requires re-observing the same population continuously, which panels cannot do.

The solution: query the classified web directly

The 102M-domain database is a census of the active web, classified into the IAB taxonomy and expanded vertical categories, with company-level attributes joined from the company database. Prebuilt slices make the common research cuts one download instead of one project.

Count the market

The industry counter answers "how many companies in vertical X" interactively; the verticals slice delivers the underlying domain list with categories and confidence scores, filterable by country and language for geographic TAM cuts.

Segment by real attributes

Intersect verticals with the technology, traffic tier, funding and hiring slices — "funded logistics SaaS with meaningful traffic that is hiring" becomes a filter expression, not a hypothesis.

Cut by business model

The SaaS, e-commerce and business model slices separate subscription software from storefronts from marketplaces — the distinction most registry codes flatten and most TAM models need.

Watch categories move

Because sites are re-classified from live crawls (see real-time categorization), diffing database releases shows entries, exits and pivots per category — a quarterly market-motion report generated from observation.

Build a market map from a domain list

Given any universe of domains — a conference exhibitor list, a portfolio, an export from the verticals slice — batch categorization turns it into a market map in one loop.

Batch categorize and aggregate (Python)
import requests, collections

API = "https://www.websitecategorizationapi.com/api/iab/iab_web_content_filtering.php"
market_map = collections.Counter()

for domain in open("universe.txt"):
    r = requests.post(API, data={
        "query": domain.strip(),
        "api_key": API_KEY,
        "data_type": "url",
    }, timeout=30).json()
    if r["status"] == 200 and r["classification"]:
        top = r["classification"][0]
        if top["confidence"] >= 0.75:
            market_map[top["category"]] += 1

for category, n in market_map.most_common(15):
    print(f"{n:6d}  {category}")
Per-domain response
{
  "classification": [
    {"category": "Business and Industrial > Logistics",
     "confidence": 0.93},
    {"category": "Technology & Computing > Enterprise Software",
     "confidence": 0.81}
  ],
  "language": "de",
  "status": 200
}

Two details matter for research use: the confidence score lets you set an evidence bar and report it in your methodology, and the language field gives you country/language distributions for free — the same loop that sizes the market also splits it geographically. For universes beyond API scale, run the same aggregation as SQL against the offline database.

From question to dataset

Typical research questions and the slice combination that answers them (figures illustrative).

Research questionData usedDeliverable
How big is the DTC cosmetics market in France?E-commerce slice × vertical × languageDomain count + full list
Which fintech niches are heating up?Funding + hiring × verticalsGrowth-signal ranking by sub-category
What share of mid-size retailers run headless commerce?Technology × traffic tierPenetration table by tier
Is the category consolidating or fragmenting?Quarter-over-quarter database diffsEntry/exit trend series
Who are the players around a target company?Competitor finder + company databaseCompetitive landscape map

Who runs this playbook

Corporate strategy

Adjacency scans and market-entry sizing: enumerate every company in a candidate category and segment by size and geography before committing to a business case.

PE / VC research

Diligence teams verify a target's claimed market with an enumerable population, then track the same population post-investment for entries and exits.

Analyst firms

Replace "based on interviews with 40 vendors" with census-backed counts — and publish the methodology, because the classification confidence threshold is explicit.

Go-to-market teams

The same slices double as targeting lists: the market map's cells are literally accounts, feeding the ICP prospecting database workflow.

Frequently asked

How current is the 102M-domain database?

Classifications come from ongoing crawls and the database ships on a refresh schedule, so quarter-over-quarter diffs are meaningful. Anything you need fresher than the last release — a shortlist for diligence, a disputed segment — can be re-classified on demand through the real-time API.

Can I map results to my own market taxonomy?

Yes. Research teams rarely think in raw IAB tiers; the taxonomy mapper translates between IAB, the expanded categories and custom category trees, so the deliverable lands in the client's language, not ours.

Do I get the domain list or just the counts?

Both. The industry counter gives instant counts; database exports include every domain with its categories, confidence scores and joined attributes, so any number in your report can be audited down to the individual companies behind it.

Related resources

Size one market on us

Tell us a vertical and a geography and we will send back a sample extract — counts, category distribution and a domain list — so you can validate coverage before building your research on it.

Try the Live Demo Request a Sample Read the API Docs
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