Diagramming Tool

No sign-up · nothing uploaded · free

The diagram tool that keeps your work in your browser

Draw cloud architecture, flowcharts, sequence diagrams and ERDs — 20 auto-layout diagram types and a free-form canvas, with 37 templates to start from. Everything renders locally and exports to PNG and SVG. No account, no upload, no watermark.

Opens straight into an editable AWS architecture diagram.

Payments platform
VPCPublic subnetPrivate subnetData subnetUsersCloudFrontLoad balancerCheckoutLedgerPostgresEvent queue

What makes it different

Most browser diagram tools ask you to make an account and then hold your work on their servers. This one does neither.

Everything you can draw

One tool for the whole set, so a system diagram and the sequence diagram that explains it do not live in two different apps.

  • AWS and cloud architecture diagrams
  • Flowcharts and process diagrams
  • Sequence diagrams
  • Entity relationship diagrams (ERD)
  • UML class diagrams
  • C4 model container diagrams
  • Kubernetes and network topology
  • State machines and user journeys
  • Gantt charts and delivery plans
  • Kanban boards and mindmaps
  • Org charts and sitemaps
  • Sankey, radar, treemap and XY charts
See every diagram type →

How it works

  1. 1

    Pick a starting point

    Press ⌘/Ctrl + K and choose from 37 real diagrams — or start from a blank canvas.

  2. 2

    Edit on the diagram

    Double-click to rename, drag a dot to connect, tap an item to open its fields. No source pane, no syntax.

  3. 3

    Export and keep it

    PNG or SVG for the document, and a .diagram.json file you own for the next time you need to change it.

Your diagrams never leave your machine

There is no diagram storage on any server here, because there is nothing to store to. Diagrams are drawn, rendered, exported and saved in your browser. Share links carry the diagram inside the URL fragment — the one part of a link browsers never transmit. Nothing expires, nothing leaks, and there is no copy of your architecture sitting in somebody else’s database.

How privacy works here →

Common questions

Is it free?
Yes — free and unlimited, with no account, no trial and no paid tier. Ads on the site pay for hosting.
Do I need to sign up?
No. There is no login. Open the studio and start drawing.
Are my diagrams uploaded anywhere?
No. Diagrams are created, rendered and stored entirely in your browser. There is no server-side diagram storage, so nothing is transmitted — including when you export or share.
Do I have to learn Mermaid or PlantUML?
No. Every diagram is edited directly on the picture. Diagram source is an internal detail you never see or write.
Can I export high-resolution images?
Yes. PNG at 1×, 2×, 3× or 4×, with a transparent, white or matching background, and SVG for anything that needs to stay sharp or stay editable.
How do I keep a diagram permanently?
Save it to your disk with Ctrl/⌘ + S. You get a .diagram.json file that belongs to you and reopens fully editable with Ctrl/⌘ + O.

What should we build next?

There is no roadmap committee here — features get built because someone asked for them. If the tool is missing something you need, or something about it is annoying you, say so.

No account needed. We ask for your email so we can actually reply — it is used for nothing else.

Documentation

Start your first diagram

Nothing to install, nothing to sign up for. The studio opens straight into a diagram you can edit.

Open the studio