Free tool · no account needed

Test your app’s magic-link login — for free

Paste your login URL and Nightlamp runs a real magic-link round-trip: it requests a sign-in email with a disposable test inbox, waits for delivery, opens the link, and measures the latency. In about two minutes you’ll know — in plain English — whether your auth-email flow actually works.

3 free runs per day. We request one login email from your app and never store its content — results auto-delete in 7 days.

what the four stages check

The whole loop your users go through

1 · Magic link requested

We load your login page, find the email form, and submit a disposable Nightlamp-owned address — exactly like a user typing their email and hitting “send me a link”.

2 · Login email received

We poll the test inbox for up to 90 seconds. No email means your users are staring at an empty inbox too — unverified senders and rate limits are the usual culprits.

3 · Login link works

We extract the sign-in link and open it once (a single GET — never anything destructive). A 404 or 500 here is the “the link you emailed me doesn’t work” support ticket.

4 · Delivery speed

Request-to-inbox latency, measured. Past ~45 seconds, users retry — and the retry often invalidates the first link they then click.

faq

Questions, answered straight

What does the magic-link tester actually do?
It loads your login page, finds the email field, submits a disposable Nightlamp-owned test address, waits up to 90 seconds for the login email to land, extracts the sign-in link, and checks that the link resolves. You get a pass/fail per stage plus the measured delivery time — the same round-trip your users experience.
What does it NOT do?
It never enters passwords, never clicks anything beyond a single GET on the sign-in link, and can't fill forms that only render via JavaScript. It also won't test URLs on private or internal networks. If your login is password-based or behind a CAPTCHA, the tester will tell you instead of guessing.
What do you store about my app?
We request one login email from your app and never store its content beyond the pass/fail result: stage verdicts, latency numbers, and the host of the URL you submitted. No email bodies, no sign-in tokens. Results auto-delete in 7 days.
Why did no email arrive in 90 seconds?
The usual causes: your sending domain is unverified with your email provider, the provider is rate-limiting you, your form silently rejects plus-addressed emails (ours looks like name+token@…), or the email job runs on a queue that's backed up. Your provider's send log for the exact minute of the test will tell you which.
How is this different from uptime monitoring?
An uptime check tells you the login page renders. It says nothing about whether the email is actually sent, delivered, and carries a working link — which is where magic-link logins really fail. This tester runs the full loop once; Nightlamp runs it for you continuously on a 15-minute schedule and alerts you the moment it breaks.

Newsletter

One real no-code incident + the fix, monthly

A post-mortem from a real no-code outage — what broke, how it was found, and the fix — once a month. Confirming also gets you the no-code incident runbook pack.

Double opt-in. One-click unsubscribe. No spam, ever.