Drop a .psd above, get a JPG of the finished design back.
Someone sent you a Photoshop file and you do not have Photoshop. A designer sends a mock-up, an agency sends artwork, a photographer sends the retouched shot, and the file will not open in anything you own. Photoshop is a subscription, and the file is already sitting in your downloads folder waiting to be looked at.
What comes out is the flattened composite. Photoshop saves a finished picture alongside the layers so other software has something to display, and that is the design exactly as the designer last saved it. Layers, masks, adjustment settings and smart objects stay in the .psd, untouched and unreadable here.
JPG is the right choice when the design is going to a person. Email it, put it in a document, print it, send it back with comments. Files run a small fraction of the .psd, which can reach hundreds of megabytes because it is storing every layer separately.
If the design has transparency, use PSD to PNG instead. JPG has no transparency and fills those areas with white, which matters for a logo and not at all for a poster.
Client work stays on your machine. Unreleased branding, campaign artwork and anything under an NDA has no business being uploaded to a stranger's server for a format conversion, and nothing here is.
A folder of mock-ups converts in one drop.