Mermaid diagram types

Mermaid timeline diagrams

A Mermaid timeline lays events out chronologically as plain text: each line is a time period followed by one or more events, and the renderer spaces them along a horizontal axis. It's the fastest way to turn a roadmap, schedule, or history into a diagram that diffs in Git and renders on GitHub.

A product roadmap grouped into quarterly sections.

Timelines are ideal when the order of things matters more than their exact dates — product roadmaps, onboarding plans, a daily routine, or the milestones of a project. In MermaidCreator you can type the syntax, edit it live, or describe the sequence and let AI draft the periods and events for you.

When to use a timeline

  • Product roadmaps and release schedules
  • Project milestones and 2-week plans
  • Daily routines, schedules, and study plans
  • Company or technology history narratives

The Mermaid code

Copy it anywhere Mermaid renders — or see the full syntax reference.

timeline
    title Product roadmap 2026
    section Q1
      Research : User interviews : Competitor analysis
      Design   : Wireframes
    section Q2
      Build    : Core editor : AI drafting
    section Q3
      Launch   : Public beta : Pricing
    section Q4
      Grow     : Integrations : Team plans

Frequently asked questions

How do I create a timeline in Mermaid?
Start a code block with `timeline`, add an optional `title`, then write one period per line followed by its events: `2026 : LinkedIn : Facebook`. The text before the first colon is the time period and each colon-separated value after it is an event. Group related periods under `section <name>` headings to colour-band them.
Can I group events into sections on a Mermaid timeline?
Yes. Add a `section <name>` line and every period beneath it is grouped and shaded together — for example `section Q1` then your Q1 periods. Sections are how you turn a flat list of dates into a roadmap with phases.
Can AI generate a timeline from a description?
Yes. Describe the sequence to MermaidCreator's AI — for example 'a 6-month product roadmap from research to public launch' — and Claude drafts the periods, sections, and events as editable Mermaid you can refine in code or with follow-up prompts.

Other Mermaid diagram types