fittings-tz-offset-at
Installation
SKILL.md
Zone rules at an instant
tz.offset-at on https://fittings.sh. One endpoint, deterministic compute.
The UTC offset, abbreviation and DST state a zone was on at any moment from 1970, with the surrounding transitions, and resolution of ambiguous or nonexistent local times.
The call
GET https://fittings.sh/v1/tz/offset-at
| Field | Type | Required | Notes |
|---|---|---|---|
timezone |
string | yes | IANA zone, e.g. America/New_York |
instant |
string | no | ISO 8601 with an explicit Z or +HH:MM offset. Give this or localTime. |
localTime |
string | no | Wall-clock time with no offset, e.g. 2026-11-01T01:30:00. Give this or instant. |
Example input: