You can limit the characters on a single-line text field by setting the maximum/minimum character limits. For this, add a single line text field on your form, and on the ‘Field Options’, click on Advance Options.

• Limit Length: Enable this option and set the number of characters or words count for the maximum number of words/characters to be allowed on the field.
• Minimum Length: Enable this option and set the number of characters or words count for the minimum number of words/characters to be allowed on the field.

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