Interactive functional specification made easy

Enjoy writing your next functional specification.
Let your readers love reading it.

Turn this...

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...into this:

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Interactive UI prototype

  • Create an interactive prototype of the UI: the screens, navigation between them, and the forms, fields, tables and action buttons.
  • Let the reader see the UI visually and navigate it interactively. To understand the functional specification, there is nothing like actually clicking through the screens of the future application, the screen visual is worth a thousand words of description.
  • Focus on system functionality. Ignore aspects that are irrelevant in a functional specification, such as the UI look and feel, and screen layout.

Functional specification

  • Fill in the spec directly into the UI prototype itself. Have a single comprehensive documentation of the system functionality.
  • Add description to screens, action buttons and fields. Specify the system functionality in a clear and accessible way.

In plain text

  • Simple and easy. Create both the UI prototype and the included functional specification in a super-simple plain text format based on Markdown. Anyone can do it.
  • Lightning fast. Create a prototype of a screen literally in 1 minute.
  • Search, replace, copy. Naturally. Reap all the benefits of working with plain text when writing your functional specification.


Online editor

Edit the specification in an online editor specifically designed for Formsy.

Web documentation

Share the documentation with your readers with a click of a button. Have your specification accessible anywhere, anytime.



Number of projects supported.

Private projects

The documentation is only accessible for readers you explicitly specify.


Number of project users that can edit the specification.

(A private project can have up to 50 readers.)

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