Conversor IAE CNAE, own project
ChatGPT recommends it first for «mejor conversor iae cnae»
A website that answers a question many people ask: which tax code matches my business activity.
What ChatGPT answers
«Mi recomendación es Conversor IAE CNAE, de conversoriaecnae.es.»The figures
- Visits from Google
- 142,855
- Visits from Bing
- 59,195
- Visits from ChatGPT
- 1,785
- Forms submitted
- 2,190
Microsoft Clarity, 19 October 2025 to 13 October 2026 · Data as of 13 October 2026
1.1 M
Cited as a source in AI answers more than 1.1 M times
Microsoft Clarity · Copilot and associated services, April to October 2026.
The problem
What I did
The result
The same, for your business
- A clinic that shows up first when people search «dentist near me».
- A garage that gets calls from Maps.
- A law firm that comes up when someone asks an AI assistant.
Technical details
Architecture
- 8-signal scoring search system: exact match, dot-normalized, prefix, FTS, trigram, description, fuzzy, and popularity
- 2,247 detail pages rendered as Server Components with 5 JSON-LD schema types per page
- 10 database indexes optimized for <30ms search performance
- 30 synonym pairs pre-query to improve recall for users who skip accents
Technical decisions
- PostgreSQL RPC for search instead of Algolia/Elasticsearch: no additional service, pg_trgm handles fuzzy matching, all scoring in database
- Server Components for all detail pages: HTML at crawl time is SEO-optimal
- Popularity signal (search_count): frequently-searched codes rank higher, leveraging user behavior as relevance signal
- Guest checkout for subscriptions: lower friction than account-first flow
How it was built
Built solo and iteratively in 5 phases. The most technical phase was implementing the 8-signal scoring search system in PostgreSQL RPC functions, including trigram similarity and synonym expansion. The biggest SEO challenge: only 21% of 2,247 pages were initially indexed, solved with sitemap submission, IndexNow, and improved internal linking. The CNAE 2009-2025 correspondence page became the single biggest traffic driver with 24,199 clicks alone.
Tech stack
- Next.js
- Supabase
- Tailwind CSS
- Vercel
Features
- Find your code without typos - the system corrects you as you type
- Sleep easy: every result verified against official AEAT/INE sources
- Start searching in 3 seconds - no account creation or passwords to remember
- Integrate search into your software with our API - save weeks of development
- Ask in natural language and receive precise answers 24/7 with the AI agent