Roll deadlines forward or back in a chosen timezone—ideal for SLAs, sprint planning, and “what time is that for UTC?” without spinning up a spreadsheet.
Result
Product and engineering estimates often sound like “ship thirty calendar days from approval,” but stakeholders live in different regions and daylight-saving regimes. This playground adds or subtracts hours, days, weeks, months, or years from a wall-clock instant interpreted in a specific IANA timezone, then shows the same instant in UTC and as a Unix epoch in milliseconds for APIs.
Weekend skipping helps rough “business day” SLAs: when enabled with day- or week-sized steps, we advance one calendar day at a time and skip Saturday/Sunday. Public holidays are not modeled—pair this with your own calendar for legal deadlines.
Are dates sent to a server? No—the calculations execute client-side for this page.
Why does my result shift when DST starts or ends? Because wall-clock math in a real zone follows DST rules; compare UTC or epoch when you need absolute duration.