# 2026-10-13 — Weekly spending limits follow ISO weeks (fix · API)

> Weekly API key spending limits reset on Monday in UTC, including across year boundaries.

Weekly [spending limits](/docs/authentication#spending-limits) now use ISO
weeks, which start on Monday at midnight UTC. The week stays together when
it spans December and January.

A key with no usage in the current period reports zero spent. A rejected
reservation also keeps the period's usage counter until the period ends.

Permalink: https://mynth.io/changelog/2026-10-13-spending-limits · Markdown: https://mynth.io/changelog/2026-10-13-spending-limits.md