Kilobytes (
kb) describe the size of electronic data or files and are routinely used in legal practice for specifying file size limits, disclosure or e-disclosure volumes, subject access request (SAR) exports, and IT or outsourcing specifications.
This is a technical unit rather than a legal term of art and is not generally defined in UK or Irish legislation or case law. In most legal and commercial documents, 1 kilobyte means 1,000 bytes (decimal, SI). Some IT contexts still use 1,024 bytes; that unit is properly the kibibyte (KiB). Where precision affects fees, service levels, bandwidth/storage commitments or filing limits, the document should state which convention applies.
The correct abbreviation is KB. Kb denotes kilobit (1,000 bits), not kilobyte. Confusing KB with Kb can significantly alter calculated data volumes and related obligations.
Usage and meaning are broadly consistent across England & Wales, Scotland, Northern Ireland and Ireland, though courts and regulators more often quote thresholds in megabytes (MB) or gigabytes (GB).