MiniPx vs Optimizilla — Upload or Stay Local — Free, Fast & Private
Optimizilla is deservedly popular: it is free, it needs no account, the interface is uncluttered, and the per-image quality slider with live preview is genuinely good — you can see exactly what you are trading before you download.
MiniPx covers the same ground with two differences that matter depending on the job: files are compressed in your browser rather than uploaded, and the format range is wider.
Batch size, honestly stated
Optimizilla handles up to 20 images per batch. MiniPx’s free tier handles 5, and Pro removes the cap entirely. So for a one-off batch of 20 holiday photos, Optimizilla is the more convenient free option and it would be silly to pretend otherwise.
The calculation changes when the work is repetitive or the batches are large: MiniPx Pro has no per-batch ceiling at all, and because nothing is uploaded, a 300-file batch is limited by your processor rather than your connection.
Formats
Optimizilla targets JPEG and PNG. MiniPx reads HEIC, TIFF, SVG, GIF, BMP, WebP and AVIF as well, and writes JPEG, PNG, WebP or AVIF. If your input is an iPhone HEIC or you want AVIF out, that is the practical difference — not a marginal one, since HEIC is what most iPhones produce by default.
Where the upload matters
For a photograph of a sunset, it does not. For a scan of a passport, a medical letter, a signed contract or unreleased product photography, uploading to any third party is a decision worth making deliberately. MiniPx removes the decision: there is no upload path in the tool.
Competitor details checked July 2026. Plans and limits change — verify against their own pricing page before deciding. Other comparisons: ImageResizer.com · ShortPixel and its credit model · remove.bg