Best Free Diagramming Tools

Free description-to-diagrams tool for developers. Create informal UML class, object, or entity-relationship diagrams using your keyword. The page we cite for this offer states no amount, tier or rate we can read when we last looked, on 2026-09-02, so we cannot confirm these terms today.

• −1 stale_verification Our last read of the vendor's pricing page, on 2026-09-02, could read no amount, tier or rate on the page. This is our confidence in the record, not a change by the vendor. (a limit of ours, not a change by the vendor)

Relationship maps with animation, decorations, filters, clustering, spreadsheet imports, etc. The free tier allows unlimited public projects. Graph size unlimited. Free private projects for students. Sandbox mode is available if you prefer not to leave your file publicly online (upload, edit, download, discard). Best for students and unlimited usage needs. The page we cite for this offer states no amount, tier or rate we can read when we last looked, on 2026-09-02, so we cannot confirm these terms today.

• −1 stale_verification Our last read of the vendor's pricing page, on 2026-09-02, could read no amount, tier or rate on the page. This is our confidence in the record, not a change by the vendor. (a limit of ours, not a change by the vendor)

interactive diagrams that allow users to see their infrastructure from multiple perspectives and levels of detail. Charts can be expressed in code. The free tier has unlimited private diagrams with up to 3 viewers. Best for unlimited usage needs. The page we cite for this offer states no amount, tier or rate we can read when we last looked, on 2026-09-02, so we cannot confirm these terms today.

• −1 stale_verification Our last read of the vendor's pricing page, on 2026-09-02, could read no amount, tier or rate on the page. This is our confidence in the record, not a change by the vendor. (a limit of ours, not a change by the vendor)

Free open-source white-boarding and diagramming tool with intelligent arrows, snapping, sticky notes, and SVG export features. Multiplayer mode for collaborative editing. Free official VS Code extension available as well. We could not read the page we cite for this offer when we last looked, on 2026-09-14, so we cannot confirm these terms today.

• −1 stale_verification We cannot confirm this offer: 2 consecutive re-check attempts have failed (most recently 2026-09-14 — page content too short (likely JS-rendered SPA); a rendering client read 205 characters), never confirmed since it was indexed. This is our inability to verify, not a change by the vendor. (a limit of ours, not a change by the vendor)

Online diagrams stored locally in Google Drive, OneDrive, or Dropbox. Free for all features and storage levels. The page we cite for this offer states no amount, tier or rate we can read when we last looked, on 2026-09-14, so we cannot confirm these terms today.

• −1 stale_verification Our last read of the vendor's pricing page, on 2026-09-14, could read no amount, tier or rate on the page. This is our confidence in the record, not a change by the vendor. (a limit of ours, not a change by the vendor)

An online diagram tool with collaboration features. Free plan with three editable documents, 100 professional templates, and basic collaboration features.

• −1 stale_verification We cannot confirm this offer: 1 consecutive re-check attempt has failed (most recently 2026-09-20 — The pricing page does not explicitly detail the features or limits of a free plan. It mentions signing up free and diagrams, but doesn't specify the number of editable documents or templates included in a free tier. It focuses on the Lucid Suite and AI features, and integrations, but lacks specific free plan details.), never confirmed since it was indexed. This is our inability to verify, not a change by the vendor. (a limit of ours, not a change by the vendor)