What is redirect latency?
When you click a shortened URL, there are two network hops instead of one. First, your browser hits the short URL server. That server looks up the destination and sends back a 301 or 302 redirect response. Then your browser makes a second request to the actual destination.
The time between the first click and when that redirect response is returned is redirect latency. For most traditional link shorteners, this is 150-400ms. That doesn't sound like much. It is.
The CTR impact you're not measuring
Google's research on search results showed that a 400ms delay reduced search volume by 0.59%. That's a search engine with massive brand authority. Your short link has none of that — it's competing on pure perception.
In email and SMS campaigns, where links are clicked on mobile networks with variable latency, an extra 300ms server delay can compound with network latency to create a 700ms+ perceived delay. Bounce rates on landing pages increase significantly at those delays.
The kicker: most link shortener analytics don't break out redirect latency separately. You see a click count drop, but you can't trace it back to the redirect server.
Why most shorteners are slow by default
Traditional URL shorteners run a central server (or a small cluster of servers) in one region. When a user in Mumbai clicks a link hosted on a server in Virginia, the request travels across the Atlantic and back — adding 150-250ms of pure geographic latency before any server processing happens.
Then the server has to query a database to look up the destination URL. Even with connection pooling and indexed queries, database reads add another 5-50ms. Add cold start times on shared hosting, and you're well above 200ms for most users outside your server's region.
The edge caching solution
ZipLink's redirect handler runs as an Edge Function — deployed to a network of data centers distributed globally. When a user in Mumbai clicks a ZipLink URL, the request is handled by a data center in Mumbai (or the nearest equivalent), not one in Virginia.
More importantly, the destination URL is cached in Upstash Redis — a globally replicated key-value store that also runs at the edge. The lookup for a cached short code is a single in-memory operation returning in under 5ms.
The result: most ZipLink redirects complete in 20-40ms end-to-end for cached links. That's an order of magnitude faster than centralized shorteners.
What this means for your campaigns
If you're running paid ads, every click you pay for is hitting your redirect server. Shaving 200ms off redirect latency means the page starts rendering 200ms sooner. On mobile, where 3-4 second page loads already strain attention, that margin matters.
For email newsletters, faster redirects reduce the perceived awkwardness between clicking and arriving — the brief 'nothing is happening' window that makes some users click away and check their inbox instead.
The fix is simple: use a link shortener that runs at the edge and caches aggressively. Your CTR will thank you.