Launching a website looks simple from the outside. From the inside, it involves dozens of tasks across three or more teams, and any one of them can block the others. Design can't finish comps until content strategy is locked. Developers can't build components until design delivers specs. Content writers can't finalize copy until the page structure is approved. QA can't test until development is done.

A Gantt chart gives you one place to see all of that at once — who's working on what, when handoffs happen, and which tasks are on the critical path to launch day.

The Five Phases of a Website Launch

Every website launch has roughly the same phases, even if the timelines differ. The Gantt chart keeps each phase visible and shows how they overlap.

Phase 1: Discovery and Strategy (Weeks 1–2)

Before anything gets built, the team needs to agree on what they're building. This phase includes stakeholder interviews, competitive analysis, sitemap definition, and content strategy. On the Gantt, these tasks run parallel. The output — an approved sitemap and content brief — is the dependency gate for everything downstream.

Key tasks:

Stakeholder kickoff and requirements gathering
Competitor site audit
Sitemap and page hierarchy draft
Content audit (if relaunching an existing site)
Brand review and design direction

The Gantt makes clear that stakeholder sign-off on the sitemap is the critical dependency. Until that row closes, design can't start wireframes and content can't start writing.

Phase 2: Design (Weeks 3–6)

Design is the phase that most often becomes a bottleneck. Wireframes need approval before visual design begins. Visual design needs approval before developers receive specs. Each approval cycle needs buffer time built in.

Key tasks:

Wireframes for key page templates (home, interior, landing pages)
Wireframe approval and revision cycles
Visual design — desktop and mobile
Design system documentation (type, color, components)
Prototype or interactive mockup for stakeholder review
Final design handoff to development

On the Gantt, build the revision cycles into the timeline explicitly. If you plan a single approval round and it takes three, the entire project slips. Two rounds of revisions is a reasonable default; schedule them in.

Phase 3: Development (Weeks 4–10)

Development typically starts while design is still in progress, beginning with infrastructure setup and front-end scaffolding that doesn't require final design assets. This is where the Gantt earns its value — showing which development tasks can start early and which must wait for design outputs.

Key tasks:

Environment setup (staging, development, CI/CD pipeline)
CMS configuration and content model
Front-end scaffolding and design system implementation
Page template development (high-priority templates first)
Third-party integrations (analytics, CRM, forms, chat)
Internal QA pass by developers

The Gantt dependency arrows here matter. Component development depends on design specs. CMS configuration depends on the content model. Third-party integrations depend on credentials being provisioned. Track each dependency or you'll find out at the end that a row is blocked.

Phase 4: Content Production (Weeks 5–11)

Content production runs in parallel with development but often slips because it feels less technical. On the Gantt, content tasks need the same rigor as dev tasks — assigned owners, due dates, and review cycles.

Key tasks:

Page-by-page copy writing (prioritized by development order)
SEO keyword mapping and on-page optimization
Image sourcing, photography, or illustration
Content review and approval by stakeholders
Content entry into the CMS
Final content proofread

The most important coordination point: content needs to be entered into the CMS before QA runs. On the Gantt, content entry has a hard dependency on CMS setup being complete, and a hard dependency relationship going the other direction — QA cannot start full testing until content is in place.

Phase 5: QA, Launch, and Post-Launch (Weeks 11–14)

QA runs in multiple passes. Development QA catches bugs during build. Pre-launch QA is structured testing against a defined test plan. Then launch itself is a coordinated event with specific steps.

Key tasks:

Test plan creation (browsers, devices, user flows)
Structured QA testing — functionality, forms, links, performance
Stakeholder UAT (user acceptance testing)
Bug fix cycles
Pre-launch checklist (redirects, meta tags, analytics, sitemap submission)
DNS cutover and go-live
Post-launch monitoring (24–72 hours)
Post-launch bug fixes

DNS cutover is a milestone on the Gantt — a single point that depends on everything before it being complete. Post-launch monitoring should be explicitly scheduled. It's not optional and it's not someone checking their email. It's a dedicated 72-hour period where someone is watching error logs, analytics, and form submissions.

Managing Cross-Team Dependencies

The biggest coordination challenge in a website launch is that three teams — design, development, and content — are all working toward the same deadline but have different tooling, different workflows, and different definitions of "done."

On the Gantt, each team gets their own swim lane. Design tasks are one color. Development tasks are another. Content tasks are a third. When a task in one lane depends on a task in another lane, draw the dependency arrow explicitly.

The common dependency chains to track:

Design → Dev: Each design template unlocks development of that template. As design delivers pages one at a time, dev can start building. This is where parallel work saves real time.
CMS → Content: Content writers can't enter pages until the CMS is configured with the right content model.
Content → QA: QA can't complete final testing until real content is in place.
All three → Launch: DNS cutover depends on QA sign-off, which depends on content being complete, which depends on dev being done, which depends on design being done.

Setting Milestones

A website launch Gantt should have four or five formal milestones — diamond markers on the timeline that signal phase completions:

Sitemap approved — triggers design kickoff
Design complete — triggers full development sprint
Development complete — triggers content entry and QA
QA sign-off — triggers launch readiness
Go-live — launch day

Milestones aren't just visual. They're accountability moments. If the "design complete" milestone slips two weeks, every downstream task and the launch date need to shift. Seeing that on the Gantt makes the impact of delays undeniable — and makes the conversation with stakeholders about tradeoffs possible before it becomes a crisis.

How Long Does a Website Launch Take?

For a small business site (10–20 pages), a realistic timeline is 8–12 weeks with a committed team. For a mid-size company site (50–100 pages), plan for 14–20 weeks. For enterprise sites with multiple stakeholder groups, compliance review, and extensive integrations, 6–12 months is common.

The Gantt won't compress these timelines unrealistically. What it does is show where you have genuine flexibility and where you don't. If stakeholder availability is limited and approval cycles take two weeks instead of one, the Gantt shows the exact impact on go-live — not as an estimate, but as a calculated shift in every downstream dependency.

Post-Launch Monitoring: Schedule It, Don't Wing It

Post-launch is the phase most teams handle informally. That's a mistake. In the first 72 hours after DNS cutover, you're likely to see:

Broken redirects for old URLs
Missing analytics tags on certain pages
Form submission failures
Performance issues under real traffic
SEO indexing questions

Schedule a post-launch monitoring block on the Gantt — a formal 72-hour period with an assigned owner who is watching dashboards, not just available in theory. After that, schedule a one-week post-launch retrospective to capture lessons and close out the project formally.

A website launch Gantt chart turns an inherently complex, multi-team project into something that can actually be managed. The alternative — tracking it across spreadsheets, email threads, and status meetings — means you find out about problems the day they blow up the launch date instead of three weeks before when you could have done something about it.