# GS1 AI (00) Serial Shipping Container Code (SSCC-18) Spec
> Validate 18-digit SSCC pallet and logistics shipping container codes in sub-1ms.

- **Canonical URL:** https://stanzaapi.com/tools/gs1-decoder/ai/00-sscc
- **Governing Standard:** GS1 General Specifications & AI Syntax (GS1 Global Standards Architecture)
- **Latency:** <1ms Edge
- **Privacy:** In-memory execution only (zero data stored or logged)

## Technical Overview & Governing Rules
The SSCC is an 18-digit identifier used to identify logistics units (pallets, shipping containers, master cartons) across supply chains.

## Specification Matrix
| Component | Length | Description |
| --- | --- | --- |
| Extension Digit | 1 digit (0-9) | Used to increase capacity |
| GS1 Company Prefix | 7-10 digits | Assigned company prefix |
| Serial Reference | 6-9 digits | Internal serial sequence |
| Check Digit | 1 digit | Modulo-10 check digit |

## Standard JSON Response Model
```json
{
  "ai": "00",
  "sscc": "001234567890123456",
  "checkDigitValid": true
}
```

## Frequently Asked Questions & Edge Cases
### Q: How is the SSCC check digit calculated?
**A:** It uses the standard GS1 alternating 3x/1x Modulo-10 checksum applied across the first 17 digits.