タイムゾーンガイド
国際予定のための記事。
How to schedule international meetings without time zone mistakes
A practical workflow for picking meeting times across countries, accounting for daylight saving and calendar rollovers.
ガイドWhat is daylight saving time and how it affects video calls
Understand DST transitions, who still observes them, and how to avoid surprise one-hour shifts on calls.
ガイドHow to use the Countries Time zone comparator
Step-by-step tutorial for comparing two to four countries with a shared reference instant.
ガイドUS time zones explained: Eastern to Hawaii
Map the six US time zones, DST exceptions, and scheduling tips for coast-to-coast calls.
ガイドCalling Latin America from Europe: practical time windows
Find workable call slots between CET/CEST and Latin American zones without ringing people at night.
ガイドUTC vs local time: what schedulers need to know
Learn when to think in UTC, when to use local wall time, and how IANA zones bridge both.
ガイドCommon time zone mistakes (and how to avoid them)
Seven frequent pitfalls—from 'EST' ambiguity to half-hour offsets—and fixes for each.
比較Time difference between Spain and Mexico (with examples)
How many hours ahead is Spain vs Mexico City? Worked examples for calls and meetings.
比較Time difference between Spain and Argentina
Spain vs Buenos Aires offsets year-round with scheduling examples.
比較Time difference between Spain and Colombia
Madrid vs Bogotá: fixed UTC-5 in Colombia and seasonal shifts in Spain.
比較Time difference between the United States and the United Kingdom
US Eastern vs London: how DST on both sides changes the gap.
比較Time difference between the United States and Japan
Tokyo vs US Eastern and Pacific with fixed JST year-round.
比較Time difference between the UK and India
London vs India UTC+5:30 half-hour offset explained.
比較Time difference between Germany and the United States
Berlin vs US Eastern and Central for transatlantic meetings.
比較Time difference between Australia and the United Kingdom
Sydney vs London across DST seasons in both hemispheres.
比較Time difference between Mexico and Brazil
Mexico City vs São Paulo for Latin American coordination.
比較Time difference between South Korea and Japan
Seoul and Tokyo share JST/KST year-round alignment.