Free online chart and diagram tools

Draw UML-style class and component diagrams from a compact text syntax with instant preview.

Shared drawing board where anyone with the link can sketch together, no sign-up.

Browser word cloud generator that lays out the most frequent terms of pasted text on a canvas.

Draw points, lines and polygons on a map and edit the resulting GeoJSON side by side.

No-code chart builder that also produces a Chart.js image URL, no login needed.

ASCII sketching app for laying out boxes, lines and labels as monospaced text drawings.

Entity-relationship diagram editor with SQL DDL import and export.

Type source-target-amount flows and get a Sankey diagram exportable as image or SVG.

Minimal flowchart editor for workflow charts, sequence diagrams and database sketches, no registration.

Browser editor that renders Graphviz DOT code into graph images with several layout engines.

Edit Graphviz graphs by clicking and dragging nodes and edges while the DOT source updates alongside.

Draws an entity-relationship diagram from pasted CREATE TABLE statements, locally in the page.

Describe systems with TypeScript-style type syntax and see the diagram; documents are saved in the browser.

Draws Graphviz DOT graph descriptions as plain-text ASCII diagrams you can paste into code comments.

Open-source mind mapping app that offers collaborative maps and sharing.

Author and test Vega and Vega-Lite chart specifications with live rendering and examples.

Draw property-graph diagrams with labelled nodes and relationships for docs or slides.

Ask questions about a chart image or have it summarized by a vision-language model.

Write concise code-like text and get an interactive sequence diagram rendered without a server.

Groups pasted timestamps by day, week or month and charts them with range filters.

Draws two- or three-circle Venn diagrams from comma-separated items.

Build line, bar, bubble, pie, donut, scatter and radar charts that are drawn locally in the browser.

Create, preview and export Mermaid diagrams as SVG or PNG in the browser.

Embeds sentences with Qwen3 in the browser and plots them on a 2D scatterplot by meaning.