# Can Records or Fields read from Extensions? **URL:** \ **Category:** Custom Extensions\ **Created:** [April 27, 2023, 7:57pm UTC](https://air.tableforums.com/t/can-records-or-fields-read-from-extensions/557 "2023-04-27T19:57:34Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![sleepyjoe](https://avatars.discourse-cdn.com/v4/letter/s/9de053/32.png) [@sleepyjoe](https://air.tableforums.com/u/sleepyjoe)\ **Post date:** [April 27, 2023, 7:57pm UTC](https://air.tableforums.com/t/can-records-or-fields-read-from-extensions/557/1 "2023-04-27T19:57:34Z")
For instance, can a formula field refer to a formula baked into the extension? Here’s the use case: I’m building an licensing app. If the user has a license key, the formula in the formula field will work. If the user doesn’t have a license key, the formula in the formula field will not work. ---
**Author:** ![Kuovonne](https://yyz1.discourse-cdn.com/flex029/user_avatar/air.tableforums.com/kuovonne/32/17_2.png) [@Kuovonne](https://air.tableforums.com/u/Kuovonne)\ **Post date:** [April 27, 2023, 8:04pm UTC](https://air.tableforums.com/t/can-records-or-fields-read-from-extensions/557/2 "2023-04-27T20:04:55Z")
> [@sleepyjoe](#): > > can a formula field refer to a formula baked into the extension Formula fields can only refer to other fields in the same table. They have no access to extensions. ---
**Author:** ![sleepyjoe](https://avatars.discourse-cdn.com/v4/letter/s/9de053/32.png) [@sleepyjoe](https://air.tableforums.com/u/sleepyjoe)\ **Post date:** [April 27, 2023, 8:08pm UTC](https://air.tableforums.com/t/can-records-or-fields-read-from-extensions/557/3 "2023-04-27T20:08:47Z")
Hm. I was wondering if someone knew something I didn’t. I know an extension can create fields/records etc. I know it can also read from records. Just trying to figure out a method that will help prevent piracy. Either way, thank you! You’re a legend, Kuovonne! Any time I see you in a thread, I know that it’s solved. ---
**Author:** ![Kuovonne](https://yyz1.discourse-cdn.com/flex029/user_avatar/air.tableforums.com/kuovonne/32/17_2.png) [@Kuovonne](https://air.tableforums.com/u/Kuovonne)\ **Post date:** [April 27, 2023, 8:19pm UTC](https://air.tableforums.com/t/can-records-or-fields-read-from-extensions/557/4 "2023-04-27T20:19:07Z")
While extensions can read and write fields and record data, the reverse is not true. Extensions also cannot create or modify formula fields. When it comes to formula fields, extensions can only read the formula results. It isn’t possible to create or edit a formula field programmatically. You can lock your extension with a license key, and then have the extension write to an editable field only if the license key is valid. However, once the data is written to the editable field, anyone can see it (unless you extension also deletes data, which I highly recommend against.) Extensions also only run when they are open. ---
**Author:** ![bfrench](https://yyz1.discourse-cdn.com/flex029/user_avatar/air.tableforums.com/bfrench/32/46_2.png) [@bfrench](https://air.tableforums.com/u/bfrench)\ **Post date:** [May 1, 2023, 2:11pm UTC](https://air.tableforums.com/t/can-records-or-fields-read-from-extensions/557/5 "2023-05-01T14:11:27Z")
> [@sleepyjoe](#): > > For instance, can a formula field refer to a formula baked into the extension? > [@Kuovonne](#): > > While extensions can read and write fields and record data, the reverse is not true. That is precisely why I have lobbied Airtable to make custom formulas through javascript possible. All I get is pushback from the community and Airtable for a capability that has existed in Google Sheets and Excel since most of you were in grade school. ---
**Author:** ![Kuovonne](https://yyz1.discourse-cdn.com/flex029/user_avatar/air.tableforums.com/kuovonne/32/17_2.png) [@Kuovonne](https://air.tableforums.com/u/Kuovonne)\ **Post date:** [May 1, 2023, 3:35pm UTC](https://air.tableforums.com/t/can-records-or-fields-read-from-extensions/557/6 "2023-05-01T15:35:45Z")
> [@bfrench](#): > > All I get is pushback from the community and Airtable I tend to try to work with what features are available now and speculate on why features have not been implemented. Coming up with reasons why things haven’t been implemented makes me less frustrated at not having them. But I’m slowly coming around to your point of view regarding custom JavaScript functions. You’ve got me believing that having formulas for all field types makes sense. Change takes time. > [@bfrench](#): > > since most of you were in grade school. Lol. I guess I’m not most people. I was out of grade school before Excel was created. I was retired before Google Sheets was created. I didn’t even know that user defined functions existed until you mentioned them, so they still feel new to me. ---
**Author:** ![bfrench](https://yyz1.discourse-cdn.com/flex029/user_avatar/air.tableforums.com/bfrench/32/46_2.png) [@bfrench](https://air.tableforums.com/u/bfrench)\ **Post date:** [May 1, 2023, 4:04pm UTC](https://air.tableforums.com/t/can-records-or-fields-read-from-extensions/557/7 "2023-05-01T16:04:14Z")
> [@Kuovonne](#): > > Change takes time. Coming up on a decade. [ticking sound] ---
**Author:** ![Kuovonne](https://yyz1.discourse-cdn.com/flex029/user_avatar/air.tableforums.com/kuovonne/32/17_2.png) [@Kuovonne](https://air.tableforums.com/u/Kuovonne)\ **Post date:** [May 1, 2023, 4:09pm UTC](https://air.tableforums.com/t/can-records-or-fields-read-from-extensions/557/8 "2023-05-01T16:09:00Z")
> [@bfrench](#): > > Coming up on a decade I was referring to having me change how I think of things taking time. Yeah, I’d like Airtable to change things faster. But I’m not in charge of making those decisions. It would be nice if Airtable took feedback from the community. But it seems to take a firestorm for Airtable to respond to community feedback, and those firestorms usually related to Airtable breaking things that used to work versus new features. This speaks of company culture.