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Best Diagramming Software in 2026

Diagramming software helps turn ideas, processes and systems into visual plans or technical diagrams. The entries are ordered in a ranking; compare them by diagram types, import/export formats and whether they support offline editing or real-time collaboration. Desktop app availability, editor seat limits and free plans can matter for how you work, while paid-from pricing adds a cost point to weigh. The first entries include draw.io, Lucidchart and Creately, with Visual Paradigm and EdrawMax also near the top. Start with the formats and diagram styles you need, then consider whether you’ll work alone, share editing or need a desktop app.

  1. 1

    draw.io

    by draw.io
    Free plan Open source WebWindowsMac+3

    draw.io offers a broad set of diagram types, collaboration, and flexible storage choices at no cost. Teams that require Enterprise SSO should note that no such tier is listed.

    9.0 Free plan Visit site
  2. 2

    Structurizr

    by Structurizr
    Free plan Open source APILinuxMac+3

    Structurizr brings model-based architecture diagrams, multiple editing options, and export tools together. Check the per-installation user bands and hosting details against your team’s requirements.

    8.6 Free plan · paid from £300/mo (annual) · 14-day trial Visit site
  3. 3

    Arcentry

    by Arcentry
    Free plan APISelf-hostedWeb

    Choose Arcentry if you need interactive infrastructure diagrams, template imports, live updates, or a way to show several providers on one canvas.

    7.6 Free plan · paid from $9.90/mo Visit site
  4. 4

    Camunda

    Free plan APILinuxMac+3
    7.6 Free plan · 30-day trial Visit site
  5. 5

    Cacoo

    by Cacoo
    Free plan APISelf-hostedWeb

    Cacoo covers a wide range of diagram types and offers collaboration, integrations, and multiple deployment options.

    7.5 Free plan · paid from $6/user/mo · 14-day trial Visit site
  6. 6

    ClickCharts

    Free plan AndroidMacWindows

    ClickCharts covers a broad range of diagram types with templates, symbols, graphing, and export options.

    7.5 Free plan Visit site
  7. 7

    Creately

    by Creately
    Free plan APILinuxMac+3

    Creately combines visual planning and diagramming with real-time collaboration, templates, and role-based sharing.

    7.5 Free plan · paid from $5/mo (annual) · 7-day trial Visit site
  8. 8

    Bizagi Modeler

    by Bizagi Modeler
    Free plan WebWindows

    Bizagi Modeler combines BPMN modeling with simulation and multiple publishing routes, including a free single-user option.

    7.4 Free plan · pricing on request Visit site
  9. 9

    EdrawMax

    by EdrawMax
    Free plan AndroidiPhoneLinux+3

    EdrawMax combines a large diagram catalogue, templates, AI tools and broad file support across desktop, browser and mobile platforms.

    7.4 Free plan · paid from $5.90/mo (annual) · 7-day trial Visit site
  10. 10

    Eraser

    Free plan APIExtensionSelf-hosted+1

    Eraser combines AI diagram creation with manual editing and team collaboration. The free plan is constrained, while private files and API calls begin with Starter.

    7.4 Free plan · paid from $15/user/mo (annual) Visit site
  11. 11

    Dia

    Free plan LinuxMacWindows

    Pick Dia if you need a free desktop diagrammer covering UML, flowcharts, networks, and entity relationships. Look elsewhere if you need a different platform or file-import route than those provided.

    7.3 Free plan Visit site
  12. 12

    Diagramo

    Free plan Self-hostedWebWindows

    Diagramo offers browser-based diagram creation, sharing, exports, and self-hosting options.

    7.3 Free plan Visit site
  13. 13

    Graphviz

    Free plan APILinuxMac+2

    Choose Graphviz if you want free, open-source graph visualization with configurable layouts and broad export options.

    7.3 Open source Visit site
  14. 14

    Ilograph

    by Ilograph
    Free plan APILinuxMac+3

    Ilograph offers interactive system diagrams, offline desktop editing, and an export route that can run without external internet access.

    7.3 Free plan · paid from $11.99/user/mo (annual) · 14-day trial Visit site
  15. 15

    D2

    Free plan APILinuxMac+3

    D2 offers text-based diagram creation with broad export, layout and editor options at no cost. Its documented scale limitation matters for very large diagrams.

    7.2 Free plan Visit site
  16. 16

    Hava

    by Hava
    Free plan APISelf-hostedWeb

    Hava combines cloud diagrams, change history, and resource-level cost estimates. Check source and user allowances against your needs, and note that exports are disabled during the trial.

    7.2 From $59/mo · 14-day trial Visit site
  17. 17

    Mermaid

    Free plan APIExtensionLinux+4

    Mermaid supports a broad range of diagram types and multiple ways to create, edit and share diagrams. Review the Basic tier’s limits and the stated browser or runtime requirements for your setup.

    7.2 Open source Visit site
  18. 18

    CloudSkew

    by CloudSkew
    Free plan Web

    CloudSkew brings diagram creation, documentation, export, and link sharing together in a web editor. Check the free plan's one-diagram limit and the stated desktop-oriented use before choosing it.

    7.1 Free plan Visit site
  19. 19

    Lucidchart

    by Lucidchart
    Free plan WebiPhoneAndroid

    Choose Lucidchart for a broad range of diagrams, real-time collaboration, offline editing, and connections to spreadsheet data.

    7.1 Free plan Visit site
  20. 20

    PlantUML

    by PlantUML
    Free plan APIExtensionLinux+4

    PlantUML offers a text-based route to many diagram types, with browser editing, integrations, and local hosting options.

    7.1 Free plan Visit site
  21. 21

    Software Ideas Modeler

    by Software Ideas Modeler
    Free plan LinuxMacSelf-hosted+1

    Software Ideas Modeler brings broad diagram coverage together with code and database modeling tools. Its edition features vary, and real-time collaboration requires Software Ideas Server.

    7.1 Free plan · 30-day trial Visit site
  22. 22

    Diagramming Tool

    Free plan Web

    Diagramming Tool offers broad diagram coverage with free, unlimited use and several export options. Save the .diagram.json version if you need to reopen and edit your work.

    7.0 Free plan Visit site
  23. 23

    IcePanel

    by IcePanel
    Free plan APIWeb

    IcePanel connects C4-style diagrams through a shared model and supports collaboration, overlays, and share links. The Free plan has editor and object caps; paid plans are billed annually.

    7.0 Free plan · paid from $40/mo (annual) · 14-day trial Visit site
  24. 24

    Pencil Project

    Free plan LinuxMacWindows

    Pencil combines interface-specific stencils, diagram shapes, and a range of export options in a desktop tool. Its links between document pages can carry through to web exports as hyperlinks.

    7.0 Free plan Visit site
  25. 25

    Preceden

    by Preceden
    Free plan AndroidiPhoneWeb

    Preceden covers timeline creation, project planning, imports, exports, and multiple sharing controls.

    7.0 Free plan · paid from $10/mo (annual) Visit site

#1Places #1, #2, #3, #4, #5 on this list can be bought by the makers of the software on it. See the price

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