Hello
I don’t find my campaign ID and I need to a discord chat bot. Can someone write a tutorial where can I find?
If only with programming can I get then please give me a source, because I am no professional programmer. Thank you. 
UPDATE: OK, it’s nothing. I used this: https://github.com/Patreon/patreon-php/blob/master/examples/patron-list.php and put campaign_id in echo.
Other quick way is to load your campaign in a web browser, View Source, and search for “campaign”. It looks like there is currently some JS pre-populated on the page that includes some API call responses which will have the campaign ID
Lol, it works. 
Thank you.
Or, if you have Chrome or Firefox (and possibly others, Edge no longer works), you can get your campaign id by going to your Patreon page (ex, http://www.patreon.com/patronizer), and then paste the following into your address bar:
javascript:prompt('Campaign ID',window.patreon.bootstrap.creator.data.id);
That will pop up a prompt that has your campaign ID highlighted and ready to be copied.
Make sure that what you paste in the address bar is preceded by javascript:, otherwise it won’t work. Both Chrome and Firefox will remove the javascript protocol when you paste the above into your address bar.
I like this solution also. Thank you that you shared your method.
The best way to do it using the API is to use the endpoint /oauth2/api/current_user/campaigns, which will give you the campaign resource along with its ID under data.id
To do the same with the actually latest version of Patreon (as of 2024. 02.), the campaign id can be accessed through:
window.patreon.bootstrap.campaign.data.id
v1 is deprecated, therefore avoid using /oauth2/api/current_user/campaigns
Use /oauth2/v2/campaigns instead.