Timezones & dates
Kickoff in UTC and in local time, because both matter.
Two clocks
Every match carries its kickoff twice. kickoff_utc is a Unix timestamp and is
the authority: use it for ordering, windows and anything arithmetic.
kickoff_local_date and kickoff_local_time are what the clock said
where the match was played.
Tottenham against West Ham on 19 October 2024 kicked off at 1729337400, which is
11:30 UTC. Locally it was a 12:30 kickoff. Both are true, and a fixture list that shows 11:30 to
a London reader is wrong.
Date filters
date_from and date_to take ISO YYYY-MM-DD and are
evaluated in UTC, inclusive at both ends. kickoff_date on a match is the UTC date,
so filtering and displaying agree.
What "today" means
For /v1/fixtures/today and /v1/results/today, today is the UTC day.
A late South American kickoff can therefore land on the following UTC date: if that
matters to you, use date_from and date_to with your own boundaries
rather than the convenience endpoint.
Seasons
A season is identified by the year it started. The 2024/25 English season is
2024. Leagues that run within a single calendar year use that year. This keeps one
integer meaningful across every competition, including the ones that run March to November.