Short.io is a well-regarded link platform that does branded domains and analytics well. KooLink is what we built. The comparison comes down to three things: price, the free tier, and whether a shortener is reachable from your AI agent.
Price
Short.io. A subscription product. There is a free trial tier, but real use — custom domains, deeper analytics, more links — sits behind a monthly plan. You pay per month and per link volume.
KooLink. Free forever. Unlimited links. No signup to shorten. There is no monthly bill and no card on file.
Signup
Short.io. An account is required. That is how the platform meters and sells its tiers.
KooLink. No account to shorten. Paste a URL, get a link. You only create an account if you want payout-linked analytics.
Custom domains
Short.io. This is a genuine strength. You can put your links on your own brand domain, which is the main reason people choose it.
KooLink. Custom branded domains are not the focus right now. The product is built for fast, free, unlimited shortening — plus the AI-agent integration.
Link tracking
Both offer analytics. The difference is price and honesty:
Short.io gives rich tracking on a paid plan. KooLink gives honest per-link views on a free plan, and filters out bot traffic rather than inflating your numbers.
The 2026 difference: MCP
This is the piece that separates the two. Short.io does not expose a hosted MCP server. KooLink does.
https://mcp.kool.ink
Point your MCP client (Claude, Cursor, Windsurf, VS Code with Continue) at it and the agent gets a shorten_url tool. Ask it to shorten any URL and it does — no browser, no copy-paste, no API key.
As agents become where work actually happens, a shortener should be inside the agent. KooLink ships that. Short.io does not.
There is a terminal one-liner too:
npx @koolink/koolink https://example.com/very/long/path
# → https://kool.ink/xyz
Bottom line
- You want branded custom domains and deep paid analytics → Short.io is a strong choice.
- You want free, unlimited, no signup, and a shortener your AI agent can call → KooLink.
If you only need a branded domain and are happy to pay, Short.io works. If you want a free, unlimited, agent-ready shortener, KooLink is the fit.