A free, local-first alternative to SimilarTech

Overview

SimilarTech is the technographic-data arm of the SimilarWeb family. Like BuiltWith, it's built for sales, RevOps and competitive-intel teams, not for developers. The product is a database of domains with attached technology profiles, surfaced through a search-and-filter UI that resembles a CRM more than a technology detector. The 'detector' framing is marketing; the real product is 'lead lists by installed technology'. SimilarTech is competent at what it does for its target customer, and mostly irrelevant to a developer looking at one page in their browser. If you have ever signed up hoping to use it as a Wappalyzer-style per-site lookup tool and bounced off the limited free tier, that is the experience working as intended — the free preview is a sales lead generator, not a developer onboarding flow.

Underneath the dashboards SimilarTech runs a periodic crawl of tens of millions of domains, tagging each with the technologies it can identify from the public homepage and a small number of subpages. The detection method is the standard fingerprint approach (headers, cookies, script-src patterns, well-known DOM markers, URL globs) plus a layer of inference from SimilarWeb's broader dataset (traffic, company metadata, vertical). Two things follow from this architecture. First, the answers are snapshot answers: whatever the crawler last saw, dated weeks or months ago, possibly missing changes you would have noticed yesterday. Second, the answers are aggregate-shaped: 'uses Stripe, uses Segment, uses Intercom' is the right granularity for a sales filter and the wrong granularity for a developer asking 'is this React 18 or React 19'. SimilarTech is a great database for the first question and structurally cannot answer the second.

History

SimilarTech spun out of the SimilarWeb ecosystem around 2014, leveraging SimilarWeb's crawl infrastructure and domain dataset to build a technographic overlay. It has always been closed-source, always been paid, and always been aimed at enterprise sales motion. Feature development over the years has concentrated on CRM integrations, ideal-customer-profile filtering, and market-share analytics rather than on deeper per-page technology detection.

The product matured during the technographics boom of the late 2010s, when sales-intelligence platforms (Bombora, ZoomInfo, Clearbit, Apollo, LeadSift) all added 'companies grouped by installed technology' as a core filter. SimilarTech's wedge was its parent dataset — SimilarWeb's traffic and company-metadata corpus made for richer overlays than competitors who had to rebuild that information from scratch. By the early 2020s the company had assembled a respectable enterprise customer base, anchored CRM integrations into HubSpot, Salesforce and Outreach, and effectively conceded the 'developer per-site lookup' market to the free tier of Wappalyzer. That positioning has not changed: in 2026 SimilarTech is still primarily a sales tool, still priced for sales teams, still indifferent to the question 'what specifically does this page use right now'.

Who uses it and for what

Sales teams use SimilarTech to build campaign lists: every domain running a specific combination of technologies, filtered by company size, industry, geography. The output of that workflow is a CSV of company names, contact metadata and the relevant technology fingerprint, exported into a CRM or sequencer for outreach. Marketing teams use it to estimate addressable markets and track competitive adoption — 'how many of our top-100 prospects added Segment this quarter' is exactly the question SimilarTech is built for.

Strategy and analyst teams use it for quarterly market-share reports, often combined with SimilarWeb's traffic data to produce stack-by-segment dashboards. Developers very rarely show up in the customer base, and when they do it is almost always because someone on the sales team granted them seat access to do a one-off 'who else uses our SDK' lookup. The product was not designed for, marketed to, or priced for the use case of sitting at a browser studying one site at a time, and a developer who ends up there usually concludes (correctly) that a free browser extension would have been a better fit.

Pricing in detail

What SimilarTech does well

Where SimilarTech falls short

These are the gaps a developer-first, sourcemap-aware workflow cares about.

Where Sourcemap Explorer wins

Not across the board — we don't run bulk API queries and we don't publish market-share dashboards. These are the things we do that SimilarTechdoesn't.

SimilarTech vs Sourcemap Explorer

Side-by-side on the dimensions a developer studying a single page actually cares about.

A concrete workflow example

You're on the engineering team of a B2B SaaS product and the founder forwards you a SimilarTech export from the sales team: a list of 200 prospect domains tagged with 'uses Segment, uses Snowflake, runs on Next.js'. The ask is technical — 'before we sequence these accounts, can we figure out which ones actually have an integration story for us'. SimilarTech got the sales team to a credible target list in five minutes; that was the right tool for the right job.

Now it is your turn. You open the first three domains in your browser, run Sourcemap Explorer on each, and within a minute per site you have the per-version Next.js detail (one is on Next 13 Pages Router and likely months from migrating, another is on Next 14 App Router and presumably ready for the integration shape you ship), the Segment SDK version (one site uses analytics-next 1.x and another is still on the legacy `analytics.js`), and a clear read on whether the team has a custom design system worth referencing in an email. SimilarTech's job was 'get us to the right 200 domains'; Sourcemap Explorer's job was 'tell us which 30 of those 200 are technically ready'. Different products, different jobs, both useful in sequence.

Which one should you use?

FAQ

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