TimezoneDB does one thing and does it well: timezone lookups. If that's all you need, it's a solid choice at $50/year. But if your application handles scheduling, international business logic, or anything involving dates across borders, you'll likely find yourself bolting on additional APIs before long.

World Data API covers the same 316 IANA timezones and adds holidays, business day calculations, and geographic data in a single integration.

TimezoneDB:

• Free tier: 1 request/second (non-commercial use only, requires API key)

• Premium: $5/month or $50/year for unlimited requests

World Data API:

Let's be direct: if you only need timezone lookups, TimezoneDB at $50/year is cheaper than our $79/year Starter plan. That's not a close call.

The calculation changes when you need holiday data or business day logic. A typical setup might combine TimezoneDB ($50/year) with a holiday API ($100+/year) and still lack business day calculations. At that point, a single API at $79/year starts making sense.

TimezoneDB's free tier allows 1 request per second, which adds up to roughly 86,400 requests per day if you sustained that rate. Our free tier caps at 60 requests per day.

For testing and development, either works. For production use on free tiers, TimezoneDB offers significantly more headroom.

Pick TimezoneDB if:

• Timezone lookups are genuinely all you need

• You want the lowest possible cost for timezone data

• You need high-volume access on a free tier

• You prefer single-purpose tools

Consider World Data API if:

• You're already planning to add a holiday API

• Your app calculates business days or working hours across countries

• You want one integration instead of managing multiple API keys

• You need geographic context alongside timezone data

Every additional API means another dependency, another API key to manage, another rate limit to track, and another potential point of failure. If your roadmap includes features like "show delivery estimate in business days" or "display local holidays," you'll end up integrating multiple services anyway.

World Data API isn't trying to compete on timezone lookups alone. The value is in having related data accessible through one endpoint.

• No formal uptime SLA (TimezoneDB doesn't publish one either, but worth noting)

• More limited free tier

• Higher annual cost for timezone-only use cases

TimezoneDB is a good API. If you need timezone data and nothing else, $50/year is hard to argue with.

If you're building something that will eventually need holidays, business day math, or geographic context, starting with World Data API means one integration instead of three.