SysML v1 available now · v2 coming soon

Model systems
in the browser.

A fast, keyboard-first SysML editor. Text and visual stay in sync. Nine diagram types, real-time collaboration, export anywhere. No install, no plugins, no lock-in.

  • Free tier forever
  • Works offline-first
  • GDPR & CCPA ready
How it works

Two ways to model. One source of truth.

Type SysML in the code panel and watch the diagram appear. Draw on the canvas and the code stays in sync. No separate export step, no hidden state.

Write SysML text

Type part def Engine { attribute mass : Real; } in the editor. The block appears on the canvas instantly. Stereotype, compartments, and all.

Draw on the canvas

Drag blocks, connect ports, auto-layout. Every edit regenerates the SysML code in the side panel. Round-trip stays exact.

Collaborate in real time

Share a link and model together. Live cursors, per-element locking, and presence badges keep everyone in sync without conflicts.

Supported diagrams

Nine views. One model.

Every diagram shares the same underlying project store. Create a block in the BDD, reference it in a Requirement, allocate it in an IBD, no copy-paste, no drift.

  • BDD

    Block Definition Diagram

    Define blocks and how they compose, inherit, and relate.

  • IBD

    Internal Block Diagram

    Wire parts together through typed ports, inside one block.

  • PKG

    Package Diagram

    Group elements into namespaces. Keep large models tidy.

  • REQ

    Requirement Diagram

    Capture text requirements and trace them through the model.

  • STM

    State Machine Diagram

    Model behavior as states and the events that move between them.

  • UC

    Use Case Diagram

    Map what users want from the system, at the level a stakeholder reads.

  • ACT

    Activity Diagram

    Describe step-by-step flow with decisions, joins, and forks.

  • SEQ

    Sequence Diagram

    Show interactions over time. Messages, returns, combined fragments.

  • PAR

    Parametric Diagram

    Bind block properties to constraints and analytical equations.

SysML v1 & v2

Pick your standard.
Move between them.

Industry hasn’t picked a winner yet. We support both, so your team can ship against v1 today and migrate to v2 on your own schedule.

Available now

SysML v1

The established OMG standard. Battle-tested across aerospace, defense, automotive, and medical devices. If your customer writes “SysML” in an RFP today, this is what they mean.

  • All nine standard diagram types
  • Full UML 2 profile compliance
  • SVG, PNG, and PDF export
  • Ships on Free and Pro plans
Start modeling in v1
Coming Soon

SysML v2

The new OMG standard, redesigned around a textual notation and a formal metamodel. Cleaner semantics, better tooling, API-first. On our roadmap. Sign up to get notified.

  • Textual notation with live visual render
  • Part / attribute / action definitions
  • KerML foundation, on the roadmap
  • API Services (2025), on the roadmap
Notify me for v2
Privacy & compliance

Privacy-first by design.

Frankfurt-hosted database, encrypted backups, Global Privacy Control honored, no third-party trackers on the editor canvas.

  • GDPREU data residency
  • CCPACalifornia rights
  • LGPDBrazil compliant
  • WCAG 2.1 AAPartial, canvas noted
  • TLS & MFATOTP, HSTS preload

Start with a blank canvas.

No install. No credit card. Sign in or model as a guest.