There is no exact resolution that you need to adhere to for your online inventory. We do however, recommend a file at high enough resolution to be viewed very clearly at full screen because many of our clients like to browse this way. As a rule of thumb, it's great to opt for a large file at 150dpi or higher.
You may upload PNG, JPG or TIFF images, however the maximum file size is 50MB.
Once a client expresses interest in your work, an Indiewalls curator will reach out to you directly via email to send a contract and for digital file transfer, so the files you upload onto Indiewalls.com will not be your final print files.