code-classify.com — 16 free, instant, in-browser tools to validate and convert the product & business codes you deal with every day, plus a deterministic pay-per-use JSON API. No signup. Same input, same output, every time — no AI guessing.
Barcodes & products
- GTIN / UPC / EAN check-digit calculator — validate or compute the GS1 Mod-10 check digit for GTIN-8, UPC-A, EAN-13, GTIN-14
- UPC ↔ EAN converter — convert UPC-A ↔ EAN-13 and build GTIN-14 case codes
- ISBN-10 ↔ ISBN-13 converter
- Bulk barcode validator — check a whole list at once
- Barcode generator — EAN-13 / UPC-A / Code 128 as SVG
- SSCC-18 calculator + GS1-128 label
Finance & banking
- IBAN checker — MOD-97 + per-country length rules
- EU VAT number validator — all 27 member states
- ISIN validator — ISO 6166
- Luhn checker (cards & IMEI)
- ABA routing number validator
Trade & logistics
- VIN validator & decoder — ISO 3779 check digit + free NHTSA decode
- ISO 6346 container number validator
- NAICS & SIC code lookup
- SIC ↔ NAICS crosswalk
- HS code lookup
Browse the full databases: NAICS directory · SIC directory
The same checks, programmatically — see code-classify.com/api (also on RapidAPI). Batch up to 100 items per call. Free tier, then pay-per-use.
Example:
curl -X POST https://codeclassify-api.rosariovitale0096.workers.dev/v1/gtin/validate \
-H "Content-Type: application/json" \
-d '{"codes":["036000291452","4006381333931"]}'
16 endpoints: GTIN validate / check-digit / convert, ISBN convert, IBAN, EU VAT, Luhn, ISIN, SSCC, container, ABA routing, VIN, NAICS / SIC / HS search, and the SIC↔NAICS crosswalk. Full docs at code-classify.com/api.
Results are computed from official public standards (GS1 Mod-10, ISO 13616, ISO 6166, ISO 3779, U.S. Census NAICS/SIC, U.S. HTS) — auditable and repeatable, unlike AI classifiers that can invent codes that do not exist. More: methodology · data sources.