Prefilling a Field in Form Builder?

[maugeri]

I am new to Airtable and created my first form a few days ago using the new Form Builder interface. After the fact, I realized there was a field I hadn't included that I'd like to prefill. 
I read through all the various instructions on prefilling by altering the URL - all makes sense to me - but I can't figure or WHERE to do the URL edit in the Form Builder interface? I can copy the form URL to the clipboard, but WHERE to I put it where the alteration to the URL will be pulished and saved?
Any guidance would be greatly appreciated. Thanks!

[Sho · Accepted solution]

Welcome Airtable Community.

The information in a prefilled URL cannot be saved in the form.
If default values are needed, there is a setting in a field on the Edit Form screen.
Prefill URL is used to share the link.

[MANCHE_NUMERIQU]

Hello,

My colleagues have just encountered a new issue induced by the UI, which strongly encourages the use of the new form creation solution in the "interface" section rather than as a classic "view".

• The old method generated public sharing links in this format: https://airtable.com/appyyy/shrxxx
  This format ending in shr accepts prefilling using "prefill".
• The new method generates public (or private) sharing links in this format: https://airtable.com/appyyy/pagxxx/form
  Apparently, this format does not allow the use of "prefill".

I find it regrettable under these conditions that the interface does not warn about the differences and/or impossibilities induced by this new way of creating forms. Airtable's official documentation on forms is also not up to date since it only deals with forms in "view" mode and not with forms created in "interface". A warning in this article would avoid misunderstandings: https://support.airtable.com/docs/prefilling-a-form-via-encoded-url#:~:text=Start%20by%20adding%20a%....

[Sho]

I have checked that pre-fill is available on the new form of interface as well.
This reference is new recently.
Building and sharing forms in Airtable 

However, the new form now saves the contents of the form as it is being filled out, so if the form is still recorded, the prefill will be overwritten. For this reason there is a Clear Form button.

I recently migrated to the new form on a trial basis, and I still don't know if this specification is good or bad.

[maugeri]

Hi Sho,

Thanks for this response! My one remaining issue: this allows for a prefill, but does not seem to allow for the prefilled field to be hidden. I can delete the prefilled field, but not hide it.

[Sho]

Is it hide by URL option?

If the value contains a string that affects the URL, it may fail to be interpreted.
( space, &, etc.).

To avoid this, there is a way to encode to UTF-8.
For formula fields, Airtable can encode them with ENCODE_URL_COMPONENT("Value").

"https://airtable.com/app~/pag~/form?" &
"prefill_Name="&ENCODE_URL_COMPONENT("value & value") &
"&hide_Name=true"

[R_Scott_Lord]

thats ninja

[HannesK-ME]

Hey everybody, I just wanted to add that our miniExtensions form has some more advanced prefill functionality, that goes well beyond what Airtable's form can do! So in addition to just prefilling fields and hiding them, you could also hide the prefill from the URL itself, so users don't see the prefill happening (and can therefore not mess with it!). This can be used in countless scenarios and can greatly improve the security of your prefills!