A feature and pricing snapshot as of mid-2026. Vendor pricing changes; confirm current numbers before buying.
| Undercart | BuiltWith | |
|---|---|---|
| Scope | Shopify commerce intelligence | Web-wide tech lookup |
| Domains / stores covered | ~2M Shopify stores | 400M+ domains |
| Technologies tracked | Shopify apps, pixels, themes, payments | ~114,000 technologies |
| Revenue estimate + confidence | ✓ | Spend/revenue attributes |
| Ad presence data | ✓ | — |
| Live catalog + inventory signals | ✓ | — |
| Nightly re-crawl | ✓ | Periodic index |
| Free single-site lookup | Free tier: 25/mo | ✓ |
| REST API | ✓ | Paid tiers |
| MCP endpoint for agents | ✓ | — |
| Chrome extension | ✓ | ✓ |
| Entry paid price | $29/mo (100 lookups) | ~$295/mo |
| Unlimited plan | $99/mo | Higher tiers |
| Filter-technology limits | No per-tech limit | Capped on lower tiers |
Sources: Undercart product data; BuiltWith pricing and knowledge base, mid-2026.
BuiltWith answers one question extremely well across the whole internet: what is this site built with? If you sell developer tooling, infrastructure, or anything that maps to a specific technology fingerprint on any platform, its breadth is unmatched, and the free single-site lookup is genuinely useful.
Undercart answers a different question about Shopify merchants: how big is this store, what is it spending on, and is it growing? It resolves revenue with a confidence score, aggregates ad presence, reads the live catalog and inventory, and re-scores nightly. For Shopify go-to-market that depth matters more than raw domain count — but it will not tell you about a WooCommerce or custom site, where BuiltWith will.
BuiltWith is a web-wide technology profiler that detects ~114,000 technologies across 400M+ domains on every platform. Undercart is a Shopify-specific intelligence tool that adds revenue estimates with confidence scores, ad-presence data, inventory signals and an API/MCP for agents. BuiltWith is broader; Undercart is deeper on Shopify commerce signals.
BuiltWith has a free single-site lookup you can run from its website or Chrome extension with no signup — useful for checking one prospect's stack before a call. List-building and export plans are paid, and 2026 pricing starts around $295/month with per-technology filter limits on lower tiers.
For Shopify specifically, Undercart is purpose-built: it estimates revenue, tracks ad presence, reads the live catalog and probes inventory, and re-crawls nightly. BuiltWith will tell you the technologies on a Shopify store but is not focused on commerce-specific signals like revenue confidence or ad libraries. For non-Shopify or cross-platform technology research, BuiltWith is the stronger choice.
BuiltWith exposes attributes like estimated spend and revenue on its paid list-building plans. Undercart makes revenue a first-class output: a composite estimate from catalog, pricing, ad spend, tech and social signals, weighted by confidence and benchmarked against a truth set, with an LLM plausibility check on very large numbers.
Both offer APIs. BuiltWith provides technology-lookup and lists APIs on paid tiers. Undercart provides a REST API plus an MCP endpoint on every paid plan — $29/month for 100 lookups or $99/month unlimited — so AI agents can query Shopify store intelligence directly with one API key.
Get 25 free store lookups with revenue, ad and catalog signals BuiltWith does not surface.