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Best Diagram Software in 2026

When you need to map a process, system, or idea, diagram software offers different ways to build and maintain a visual representation. Compare diagram types and import and export formats, then consider desktop app availability, maximum editors, real-time collaboration, and version history. Free-plan availability and paid-from pricing can also help frame the choice. draw.io, EdrawMax, and Creately are among the entries, alongside Buddi and Lucidchart. Whether you work solo or with others, the listed editor limits and collaboration features can help you assess how each option may fit your diagramming workflow.

  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.

    9.1 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

    Archi

    Free plan LinuxMacWindows

    Archi offers ArchiMate modelling and extensible tools across Linux, macOS, and Windows at no charge.

    7.6 Free plan Visit site
  4. 4

    Creately

    by Creately
    Free plan APILinuxMac+3

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

    7.6 Free plan · paid from $5/mo (annual) · 7-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

    Eclipse Papyrus

    Free plan LinuxMacSelf-hosted+2

    Eclipse Papyrus offers desktop and browser-based modeling, customization, and a broad set of listed standards. Users should account for the Java 21-compatible JVM requirement for Papyrus.

    7.5 Free plan Visit site
  7. 7

    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
  8. 8

    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.

    7.4 Free plan 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

    Graphviz

    Free plan APILinuxMac+2

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

    7.4 Open source Visit site
  12. 12

    Cloudcraft

    Free plan APIWeb

    Cloudcraft combines live infrastructure diagrams with incident, security, and cost views.

    7.3 Free plan Visit site
  13. 13

    Lucidchart

    Free plan AndroidAPIExtension+2

    Lucidchart covers a wide range of diagramming tasks, with collaboration, AI prompts and data links. The Free plan has document and shape limits; Individual costs $9 a month.

    7.3 Free plan · 7-day trial Visit site
  14. 14

    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
  15. 15

    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
  16. 16

    Diagram Designer

    Free plan Windows

    Diagram Designer combines diagram drawing with several built-in utilities and broad image-format support. Check the listed Windows versions and the limited documentation before choosing it.

    7.1 Free plan Visit site
  17. 17

    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
  18. 18

    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
  19. 19

    Modelio

    Free plan LinuxSelf-hostedWindows

    Choose Modelio if you need a free modeling environment with several architecture and engineering standards, consistency checks, and extensibility options.

    7.0 Free plan Visit site
  20. 20

    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
  21. 21

    ProcessOn

    Free plan AndroidiPhoneWeb

    ProcessOn brings diagram creation, cloud saving, collaboration, and AI tools together in a web-based service. Check the free plan's file, collaborator, and download-format limits against your needs.

    7.0 Free plan · 7-day trial Visit site
  22. 22

    Sparx Enterprise Architect

    by Sparx Enterprise Architect
    Free plan APILinuxMac+3

    Enterprise Architect combines modeling, requirements traceability, simulation, code engineering and collaboration in one tool.

    7.0 Free plan · 30-day trial Visit site
  23. 23

    Holori

    Free plan Web

    Holori combines cloud cost visibility, cost allocation, recommendations, and infrastructure documentation. Check the monthly spend limits and automatic plan upgrades when choosing a tier.

    6.9 Free plan · paid from $49/mo · 14-day trial Visit site
  24. 24

    yEd Graph Editor

    by yEd Graph Editor
    Free plan LinuxMacWindows

    yEd offers broad diagram formats and layout options at no charge, with desktop versions for three operating systems.

    6.8 Free plan Visit site
  25. 25

    Astah Professional

    Free trial APILinuxMac+1

    Astah Professional combines diagramming, code support, and model comparison tools in a desktop application.

    6.6 Free plan · paid from $6.99/mo · 20-day trial 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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