what should be the image size of featured image in wordpress?
You should select as per your Theme requirement.
1.I want homepage image as 340*248 but also shows same size in my post page as well. what if i want to show that image in big size then that featured image?
First off, Please check your Theme Option. Mostly comes in image resizing option and alignment option.
how to check that?
Login to WordPress Dashboard > Go to Theme Options if there is present.
For example, I see Genesis as option in my case.
what to do I have astra free theme
Check in the theme documentation.
there are options but not of changing image options as i want. what i do bcoz my homwpage images are larger then other website
No theme will have everything you want. Use custom CSS etc. To make it look like you want.
Reduce their resolution?
How to do that? Give me some solution for that?
Disclaimer: Below steps should be proceeded only after taking backup.
Steps to set custom image size in the Astra theme
Step 1. Login to Dashboard > Go to Media settings > Change Large size height and width.
Step 2. Check your homepage
Step 3. Regenerate Thumbnail to have optimized image size in px.