--- title: "Test sign-up and login emails in Lovable apps · Proxy Mail QA" description: "Lovable apps sign people in with Lovable Cloud or Supabase. See which logins send email, fix links to localhost and missing emails, and test each one." url: https://proxymail.qa/built-with/lovable --- 1. [Home](https://proxymail.qa/) 2. [AI app builders](https://proxymail.qa/built-with) # Testing sign-up and login emails in Lovable apps Lovable can add accounts to your app in a single prompt. Most apps use Lovable Cloud, its built-in backend; some connect their own Supabase project. Either way, the confirmation, code and password-reset emails are the first thing new users see, so check them before you share your app. Updated 15 October 2026 ## Your login options in Lovable Lovable Cloud uses email sign-in by default, and you can add others under **More → Cloud → Users → Auth settings**. Here’s which ones send email: | Sign-in option | Emails your users get | Test with Proxy Mail QA | | -------------------------------- | ------------------------------------------ | ---------------------------- | | Email and password (the default) | Confirmation, password reset, email change | Yes | | Email codes | A code to sign in | Yes, with a Copy button | | Magic links | A link to sign in | Yes | | Invites (Add user) | An invitation | Yes | | Google, Apple or Microsoft | None to sign in | No: use an account you own | | Sign in with Lovable | None from your app | No: use your Lovable account | | Phone | A text message | No | | SAML SSO | None to sign in | No | New to these? [Login methods explained](https://proxymail.qa/built-with/login-methods) covers what each one does and what usually breaks. ## Test every login email in five minutes 1. **Create an address** in Proxy Mail QA, with a generated persona if your form asks for a name. 2. **Sign up on your published app,** not only in the editor preview. 3. **Use the link or code from the row.** A confirmation link gets **Open link** and **Copy link** buttons; codes get a **Copy** button. 4. **Then test the rest:** sign out, request a code, magic link or password reset, and use those too. 5. **Save the password** on the row so you can sign in as this user again later. ## The two settings that break Lovable login emails **1\. The Site URL.** Login emails build their links from it. On **Lovable Cloud**, Lovable sets it to your published `lovable.app` address when you publish and adds custom domains to the redirect list, unless you’ve set a Site URL yourself: check it under **Auth settings → Advanced**. On **your own Supabase project**, nothing updates automatically. Open **Authentication → URL Configuration**, set **Site URL** to your published address or custom domain, and add the others under **Redirect URLs**. Otherwise confirmation links send people to `localhost:3000`. Proxy Mail QA flags those links, including hosted Supabase links that only redirect to localhost after verifying. [Full guide](https://proxymail.qa/solve/localhost-links). **2\. The email sender.** On **Lovable Cloud**, login emails come from a generic sender until you set up your own domain under **More → Cloud → Emails**, so your users recognise who they’re from. On **your own Supabase project**, the built-in sender is for development: it sends only 2 emails an hour, and only to members of your Supabase project’s team, so mail to a test address never leaves Supabase. Set up **custom SMTP** with a provider such as Resend before you test with outside addresses or launch. [Other reasons email doesn’t arrive](https://proxymail.qa/troubleshooting). ## Ask Lovable for the fix Once you’ve seen the problem, a precise prompt works best: “Use the current site’s address as the email redirect for sign-up and password reset, instead of a hard-coded URL.” Then sign up again with a fresh address to confirm. ## Copy-paste prompts for Lovable Prompt ```text List every email this app sends: sign-up confirmation, magic link, password reset, invite and email change. For each, tell me what triggers it, which URL its link points to, and how long its link or code stays valid. Flag anything that uses localhost. ``` Prompt ```text Use the current site's address as the email redirect for sign-up, magic links and password reset, instead of a hard-coded URL. After a password reset, send the user to a page where they choose a new password, then sign them in. ``` Prompt ```text Show a clear message when a confirmation or reset link has expired or was already used, with a button to send a new one. ``` ## Try it on your next sign-up test Free plan, no credit card. Create an address and watch the code or link arrive. [Create a free account](https://app.proxymail.qa/?mode=signup&from=lovable) ## Questions ### Why does my Lovable confirmation email link to localhost:3000? Usually because the app uses your own Supabase project, whose Site URL starts as http://localhost:3000\. Set it to your published Lovable address or custom domain under Authentication, URL Configuration. On Lovable Cloud, Lovable sets the Site URL when you publish, unless you set one yourself: check it under Auth settings, Advanced. ### Why aren't my sign-up emails arriving? If you connected your own Supabase project, its built-in email sender only delivers to members of your Supabase project's team, and only 2 emails an hour: set up custom SMTP, for example with Resend. On Lovable Cloud, check you haven't reached the sending limits set in Auth settings. ### Users get "Email not confirmed" when they sign in. Why? Email confirmation is switched on, so accounts can't sign in until the link in the confirmation email is clicked. Test the full sign-up with a Proxy Mail QA address to make sure that email arrives and its link works. ### Can I test Sign in with Google? Not with Proxy Mail QA: Google handles that sign-in and sends no email. Use a Google account you own, on the published app as well as the preview. ## Related guides - [ReplitReplit Auth, Clerk Auth or your own: which send email, and how to test each on the published app.](https://proxymail.qa/built-with/replit) - [BoltTurn on email confirmation, fix the localhost Site URL and test every auth email before you publish.](https://proxymail.qa/built-with/bolt) - [Base44Test the sign-up code, password reset and invites, and every user role, with a test account per role.](https://proxymail.qa/built-with/base44) - [v0Set Supabase’s Site URL and redirects for Vercel deployments, or move Clerk to production, then test every login email.](https://proxymail.qa/built-with/v0) - [Claude CodeCheck the auth emails in apps you build with Anthropic’s coding agent, from localhost to staging.](https://proxymail.qa/built-with/claude-code) - [OpenAI CodexRun the real email flow once before you merge a Codex change that touches sign-up or login.](https://proxymail.qa/built-with/codex) - [QoderCheck the real sign-up, code and reset emails after the agent changes your auth code, or let it check them itself.](https://proxymail.qa/built-with/qoder) - [CursorCheck the real sign-up, magic-link and reset emails after the agent changes your auth code.](https://proxymail.qa/built-with/cursor) - [Google AntigravityKeep unverified Firebase users out, check authorized domains and the sender, and let the agent run the check.](https://proxymail.qa/built-with/antigravity) - [Login methods explainedEmail, codes, magic links, Google and Apple buttons, phone and SSO: what each sends, what breaks and how to test it.](https://proxymail.qa/built-with/login-methods) [See every email testing problem we solve](https://proxymail.qa/solve) Lovable is a product of Lovable. Supabase is a trademark of Supabase, Inc. Proxy Mail QA is independent and isn’t affiliated with or endorsed by them.