Hey ​@soumya!

Unfortunately that is not possible using Airtable native forms. However, you can for sure achieve this using Fillout forms (free plan is super generous, and you get a direct Airtable integration) -see image below. You can find a detailed comparison between Aritable native forms and Fillout forms here.
 

However, if you still want to stick to Airtable:

The best you can achieve using Airtable forms is to have the “error message” once the max amount has been met. As a workaround (not dynamic) you could have the max character allowed on the helper text of the question.
 

 
See config below:
 

Hope this helps! Please let me know if I can help in any way.

Mike, Consultant @ Automatic Nation

​@soumya 

​@Mike_AutomaticN gave you some great resources to learn about Fillout’s advanced forms for Airtable, and I also created 2 videos (below) about Fillout as well.

Fillout is the best free “add-on” for Airtable, because it offers hundreds of features that Airtable’s native forms don’t offer, including the ability to update Airtable records using a form, display Airtable lookup fields & attachments on a form, control access to a form via SSO or email domains, perform math or other live calculations on your forms, accept payments on forms, collect signatures on a form, create multi-page forms with conditional paths, create new linked records on a form, connect a single form to dozens of external apps simultaneously, add CAPTCHAs to your form, and much more.

I show how to use a few of the advanced features of Fillout on these 2 Airtable podcast episodes:

• Using Fillout to create an eSignature approval process with PDF file creation.
• Using Fillout to create an order entry form with line items.

Hope this helps!

If you’d like to hire the best Airtable consultant to help you with anything Airtable-related, please feel free to contact me through my website: Airtable consultant — ScottWorld