Conversor de fuso horário

UTC — the universal anchor. Coordinated Universal Time (UTC) is the basis for all civil time zones. Every time zone is defined as a fixed or seasonally varying offset from UTC. Aviation, GPS satellites, and internet infrastructure all operate on UTC, making it the common language of time across industries and borders. Unlike time zones with DST, UTC never changes — which is why it is the preferred reference for logging events, scheduling across regions, and database timestamps.

The IANA timezone database. Behind every accurate time conversion is the IANA Time Zone Database (also called tz database or zoneinfo), the authoritative global record of time zone rules. It documents every historical change, current DST schedule, and future planned adjustment for over 400 named time zones. TimeandTool uses the IANA database via the JavaScript Intl.DateTimeFormat API, so results reflect real-world DST transitions — including edge cases like the US spring-forward in March and the EU autumn clock-change in October.

Daylight saving time — what changes and what doesn't. Approximately 70 countries observe daylight saving time, typically shifting clocks forward by one hour in spring and back in autumn to extend evening daylight. However, the dates differ by hemisphere and country: the US and Canada change clocks on different Sundays than the European Union, and countries like Australia change in September (spring in the southern hemisphere). Many regions — including India, China, Japan, the UAE, and most of Africa — never change clocks, making them simpler anchors for international scheduling.

Why time zones matter for global business. A one-hour scheduling error caused by a DST transition or incorrect offset assumption can result in missed meetings, delayed deployments, or compliance failures. For remote teams spanning multiple continents, establishing a shared UTC-based schedule and always confirming times with full offset notation (e.g., “Monday 15:00 UTC”) eliminates ambiguity. Use our Meeting Planner to find business-hours overlap across up to six cities simultaneously.

Methodology: All UTC offsets and DST indicators on this page are computed using the Intl.DateTimeFormat API with the IANA timezone database built into the V8 JavaScript engine. The reference table uses January 15, 2026 as a fixed winter date to avoid DST ambiguity.