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 2026-10-12, so we cannot confirm these terms today.

• −1 stale_verification Our last read of the vendor's pricing page, on 2026-10-12, 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)

Online diagrams stored locally in Google Drive, OneDrive, or Dropbox. Free for all features and storage levels. The page we cite for this offer does not name it when we last looked, on 2026-10-28, so we cannot confirm these terms today.

• −1 stale_verification We cannot confirm this offer: 1 consecutive re-check attempt has failed (most recently 2026-10-28 — the page never names diagrams.net, on a domain that carries its name), 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)

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. When we last read the page we cite for this offer, on 2026-11-04, we found a change we could not reconcile with the terms we publish, so we cannot confirm these terms today.

• −1 stale_verification Our last read of the vendor's pricing page, on 2026-11-04, found the page different from the terms we hold. This is our confidence in the record, not a change by the vendor. (a limit of ours, not a change by the vendor)

Collaborative whiteboard — 3 editable boards, unlimited team members, 10 AI credits/month, 5 Talktracks, 250+ app integrations including Microsoft, Slack, Google, and Adobe. When we read the page we cite for this offer on 2026-10-16, we refused the change we considered recording because it named no figure that had moved, and we have read it again since, on 2026-11-07, without confirming the terms above, so we cannot confirm these terms today.

• −1 stale_verification Our last read of the vendor's pricing page, on 2026-11-07, found the page different from the terms we hold. 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 2026-11-09, so we cannot confirm these terms today.

• −1 stale_verification We cannot confirm this offer: 8 consecutive re-check attempts have failed (most recently 2026-11-09 — 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)

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: 4 consecutive re-check attempts have failed (most recently 2026-11-10 — The pricing page text provided does not contain any plan details, tier limits, or pricing information for Lucidchart's Free plan (or any plan). It only shows marketing content, features, integrations, and calls to sign up, so the stored deal info cannot be verified against it.), 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)