How to change the length of data which can be stored within a label

How to change the length of data which can be stored within a label.

Any

These fields are core out-of-the-box elements protected from migration via update sets and amending them may result in issues in the future as you upgrade your instance.

Increasing the label length is not recommended! There should not be any need to increased beyond 80 Chars.

There are other options such as:

1.  If you want users and customers to enter data into fields of a record, use a record producer.
   
   The Catalog Builder tool can create a Record Producer for any task-based table and you can select columns to add as Variables to the Record Producer. The Variables each have a "Question" field that has a default length of 255 characters and can be used to prompt the user with a question. For more info on these tools, see the following documentation links.
   
   Catalog Builder | Record Producer | Service Catalog Variables | Creating Record Producers From Tables
   
   
2. If you have a high level user / admin that wants to know more info about a field's data, add hints to the label field.
   
   The Hint field can be used to show longer text when a user hovers their mouse over a field label.
   
   Change Field Label Or Hint