Most launch problems are not surprises. They are skipped steps. This checklist covers the things that actually break and the checks worth running before you flip the switch.
Functionality Testing
Click every link. Submit every form. Run through the checkout flow end to end. Test API integrations with real requests, not just the happy path. If you have database writes, verify the data lands correctly. Anything that moves data between systems needs a manual pass before launch.
Content Verification
Read the copy out loud. Spell check misses things your eyes skip. Make sure images load at the right size and are not being stretched or cropped badly on mobile. Check that your privacy policy, terms, and any legal copy reflect the current product, not a template you forgot to edit.
Performance Testing
Run PageSpeed Insights and actually look at what it flags. Check load time on a throttled connection, not just your office wifi. Large uncompressed images are the most common culprit. If you expect traffic spikes, test under load before launch, not after.
Security Checks
SSL should be on and the cert should be valid. Confirm HTTPS is enforced and HTTP redirects properly. Check that any admin or protected routes require authentication. If you collected user data during development, make sure it is not sitting in a publicly accessible database or test environment.
Compatibility Testing
Test on at least one real mobile device, not just a browser emulator. Check Chrome, Firefox, and Safari at minimum. Resize the browser window and make sure nothing breaks at common breakpoints. If accessibility matters to your audience, run an automated scan with axe or a similar tool.
SEO
Every page needs a unique title tag and meta description. Images need alt text. Check that your canonical tags are set, robots.txt is not blocking pages you want indexed, and your sitemap is up to date. Submit to Google Search Console before launch so indexing starts from day one.
Analytics and Monitoring
Verify your analytics tag is firing on every page before you push live. Set up uptime monitoring on something external so you get alerted if the site goes down. If you have error tracking (Sentry, Datadog, etc.), confirm it is connected and sending alerts to someone who will actually see them.
Backup and Recovery
Take a full backup before you launch. Know where it lives and how to restore from it. If something goes wrong in the first 24 hours, you will want to be able to roll back in minutes, not hours.
The checklist is not glamorous. But a broken form on launch day or a missing SSL cert costs more time than running through these checks ever will.