A consistent PuTTY window size prevents unexpected line wrapping, keeps full-screen tools readable, and makes copied terminal output more predictable across sessions.

The initial PuTTY window size is defined as a character grid using Columns (width) and Rows (height). Those values are stored inside a session profile, so the same host can open with different dimensions depending on which saved session is used.

Sizing is not pixel-perfect because the visible window depends on the selected font metrics and Windows display scaling. Changes apply only to the loaded profile until saved, and choosing Default Settings updates defaults for new sessions rather than retrofitting existing saved sessions.

Steps to set a custom window size in PuTTY:

  1. Launch PuTTY.
  2. Select the session profile to change in Saved Sessions.

    Select the specific saved session to change one profile, or select Default Settings to change defaults for new sessions.

  3. Click Load.
  4. Select Window in the Category tree.
  5. Set the Columns value under Set the size of the window.
  6. Set the Rows value under Set the size of the window.

    Columns and Rows are character cells, so the physical size changes with the configured font size and Windows DPI scaling.

  7. Select the preferred option under When window is resized.

    Change the number of rows and columns keeps font size fixed, while Change the size of the font keeps rows/columns fixed.

  8. Select Session in the Category tree.
  9. Enter the session name in the Saved Sessions field.

    Keep the same name to overwrite the existing profile, or enter a new name to create a separate profile with the new window size.

  10. Click Save.
  11. Click Open to start a session using the saved profile.
  12. Confirm the remote terminal reports the expected size.
    $ stty size
    40 120