Form guides

Prefill a form

Add field IDs and values to a public form URL. The answers appear when someone opens the link.

Create a prefilled link

  1. Copy the public link from your form's Share page.
  2. In the form editor, select a field and copy its Field ID. Use the ID as the parameter name, not the question label.
  3. Add ?fieldId=value to the link. Join more parameters with &.

Examples

Replace the slug and sample IDs with your own.

One field 
https://filly.app/f/your-slug?ab12cd34ef=Ada
Multiple fields 
https://filly.app/f/your-slug?ab12cd34ef=Ada&gh56ij78kl=Toronto
Multiple choices in one field 
https://filly.app/f/your-slug?mn90op12qr=Design&mn90op12qr=Engineering

Repeat the same ID for each selected option in a multi choice field. Option values must match the form's option text exactly. Encode spaces and special characters in URLs, for example Ada%20Lovelace.

Supported fields

  • Short text, long text, and email without required sign-in.
  • Number within the field's minimum and maximum.
  • Rating as a whole number from 1 to the field's maximum.
  • Date in YYYY-MM-DD format.
  • Single choice, multi choice, and dropdown using exact option text.

Images and email fields that require sign-in cannot be prefilled. For supported fields, accepted URL values replace saved answers. People can edit the answers before submitting.

Prefilled values are visible in the URL. Avoid sensitive information.