Conversor IAE CNAE
conversoriaecnae.es
Avoid tax penalties: convert IAE-CNAE codes with legal precision
The only tool with 2,247 official codes, smart search, and complete legal compliance to classify your business activity.
175K+
Verified clicks (GSC)
from March to December 2025
4.5M
Google impressions
average position 4.2
88.7%
Desktop traffic
professional tool
The Challenge
An incorrect tax code can cost you a fine from AEAT. Thousands of freelancers waste hours searching official PDFs without finding the correct IAE-CNAE equivalence.
The Approach
Instant search with typo tolerance and real-time suggestions. Results verified against the 13 official AEAT equivalence tables, directly downloadable.
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
Key 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.
Results
From zero clicks in February to 175K annual clicks by December 2025. March brought first signal (517 clicks, position 36). April showed breakthrough (3,583 clicks, position 7). May exploded to 20,193 clicks when the mandatory CNAE 2025 transition created urgent demand. June peaked at 27,790 clicks. After the seasonal summer drop, September recovery proved ranking durability. December closed with average position 4.2, the best of the year.
Tech Stack
What you get
- 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