A salon portfolio sells on detail: the edge of a fade, the line where a balayage melts into a root, the cuticle work on a nail set, the exact shade of a gloss. That is the opposite of what generic compression protects. Most tools optimise for a smooth sky or a face at arm's length, both of which survive aggressive quality reduction, while fine texture and hair strands disappear first. The second constraint is per-platform resolution guidance, not size. Fresha recommends 2727 x 1545 pixels for service portfolio images with a minimum of 1818 x 1030, and explicitly calls out sharpest results at 3636 x 2060 — a phone photo shot in portrait is the wrong shape for that frame and a heavy downscale lands under the minimum. Fresha also caps manual portfolio uploads at 10 images per batch, so a hundred-photo portfolio is ten uploads no matter what. Vagaro is tighter still: up to three portfolios with three images each, a service image capped at 4MB at roughly 798 x 894, and a logo that must be at least 1000 x 667 pixels and no more than 5MB. Meanwhile Booksy asks only for JPEG or PNG at high resolution with no published size cap, and StyleSeat takes JPEG, PNG and HEIC up to 14MB per photo. The work is therefore not one global setting: it is resize to the platform's frame, compress to a quality that keeps hair and nail texture, and keep the aspect ratio landscape where the placement is wide. Skwish does resize, format conversion and quality control in the browser with a per-file before/after readout, and packs the finished set into one ZIP so a portfolio upload is one pass instead of ten.