PromoClock: Timezone Tracker for Claude's 2x Off-Peak Hours Built with Claude 4.6
A developer has built PromoClock.co, a free timezone tracker specifically for Claude's 2x off-peak promo hours. The tool solves the daily annoyance of manually converting the published "5-11am PT / 12-6pm GMT" windows into local time.
How It Works
The website automatically detects a user's browser timezone and displays whether the 2x limits are currently active. It provides a countdown to the next status change.
Technical Build with Claude 4.6
The developer used Claude Opus 4.6 to build the entire project. Key implementation details from the source include:
- Timezone Logic: Claude wrote complex JavaScript using the
Intl.DateTimeFormatAPI to accurately convert PT/GMT hours to local browser time, correctly accounting for recent US Daylight Saving Time changes. - Next.js 15 & i18n: Claude architected the Next.js 15 App Router setup, including a lightweight Server Component-based i18n middleware to support 10 languages without bloating the client bundle.
- UI & Logo: Claude generated pure SVG code for the logo and styled the interface using Tailwind CSS based on a "minimalist/calm" design prompt.
- API & Tools: Claude helped create a
/api/statusJSON endpoint for terminal users and a dynamic.icscalendar generator to sync the 2x windows with personal calendars.
The tool is completely free with no advertisements.
📖 Read the full source: r/ClaudeAI
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