Container Number Validator
Validate ISO 6346 container numbers with check digit verification. Paste one or many — results are instant.
One per line or comma-separated. Spaces are ignored.
How Container Numbers Work
ISO 6346 Standard
All shipping containers follow the ISO 6346 standard for identification. The format is always 4 letters + 7 digits (11 characters total). The last digit is a check digit computed from the first 10 characters using a weighted sum algorithm. This detects typos and transposition errors that could cause containers to be misdirected.
The Fourth Letter
The fourth letter indicates equipment category: U = freight container, J = detachable equipment, Z = trailer/chassis. Most shipping containers end with "U" (e.g., MSCU, HLCU).
Why Check Digits Matter
A single digit error can route a container to the wrong terminal or the wrong country. Misdirected containers cost $1,000+ to recover and can delay entire shipments. Always verify check digits before submitting to customs or carriers.
Processing Hundreds of Containers?
CargoMode extracts container numbers from packing lists automatically — validated, enriched, and ready to sync to CargoWise in seconds.
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