Same compression quality. Your photos never leave your Mac. No upload, no 5 MB limit, no batch cap, works offline.
Verdict
TinyPNG is a beloved web service that compresses well — but every image you drop into it leaves your Mac and lands on their servers. Kompressor does the same compression job, on the same Mac, with no upload, no 5 MB limit, no 20-image batch cap, and no internet required. For privacy, big batches or working offline, Kompressor wins. For one-off compression with no install, TinyPNG still works.
| Feature | Kompressor | TinyPNG (web) |
|---|---|---|
| Price | $2.99 one-time | Free up to 20 imgs / batch · API from $25/mo |
| Free tier | 10 images / day | 20 images / batch, max 5 MB / file |
| Platform | macOS 11+ native app | Web only (+ WordPress, Photoshop plugins) |
| Privacy | 100% local — never uploads | Uploads to servers |
| Internet required | No, fully offline | Yes, always |
| Per-file size limit | None | 5 MB |
| Batch cap | Unlimited | 20 / batch (web) |
| Output formats | JPEG, PNG, WebP | JPG, PNG, WebP |
| Resize | 5 presets + original | Pro plans only |
| Drag & drop folder | Yes, recursive | No (file-by-file in browser) |
The single biggest reason to skip TinyPNG and pick Kompressor is privacy. TinyPNG is a web service: every image you drop on their site is uploaded to their servers, compressed there, and sent back to you. Their privacy policy is reasonable, but the fundamental fact does not change — your private photos, client mockups, internal screenshots, draft brand assets all travel through someone else's infrastructure. Kompressor processes everything on your Mac. No upload, no telemetry, no third party. You can compress sensitive client work on a locked-down corporate Mac without filing a vendor security review first.
TinyPNG's free web tier caps you at 20 images per batch and 5 MB per file. Modern phone photos and DSLR exports routinely exceed 5 MB; a single full-resolution iPhone shot can hit 8–12 MB. So TinyPNG either rejects them or you have to manually pre-resize. Kompressor has neither limit. Drop a folder of 500 photos at any size; it eats them in one batch and writes 500 lighter copies in seconds. The free tier (10 / day) refreshes every day, no card needed.
TinyPNG fundamentally cannot work without internet — the processing happens on their servers. Kompressor uses your Mac's CPU. Compress fifty conference photos on a plane, edit a deck on the train, prepare images for a client meeting in a basement office without bars. Nothing changes. The app does not care if you are connected.
TinyPNG's web interface is simple but limited: drag images
one by one (or up to 20 at a time) into a browser window,
wait for upload, wait for compression, wait for download,
save to disk. Kompressor lives in macOS the way a Mac app
should — drop a Finder folder onto the window, watch the
file list populate, hit Compress, find the results in
~/Documents/Kompressor/ with a
-kompressor suffix. No browser tab, no
download dialog, no rename dance.
TinyPNG is a website. Open it in any browser on any operating system, drop an image, get a smaller one. No download, no install, no Mac required. For a Linux laptop, a friend's Windows PC, or a one-off compression where you don't want to install anything, TinyPNG is the right tool. Kompressor is macOS only and requires a 6 MB install.
TinyPNG's WordPress plugin is one of the most popular image plugins in the ecosystem — it auto-compresses images on upload and bulk-compresses media libraries through their paid API. Their Photoshop plugin slots into export workflows. If your job involves a CMS pipeline or Photoshop-driven export, those plugins are genuinely useful and Kompressor has no equivalent (yet).
TinyPNG's paid API (from $25/month for 10,000 images) is rock-solid for server-side compression in CI/CD pipelines, static site generators, or ETL flows. Kompressor is a desktop app — there is no API. If you need to compress images from a Node.js script that runs on a Linux box, TinyPNG's API is the right tool.
TinyPNG's web tier is free for up to 20 images per batch. Beyond that, paid plans start at $25 per month for 10,000 API images, scaling up to enterprise. Their WordPress plugin is free for the first 500 images per month, then $0.009 per image.
Kompressor is $2.99 once for one Mac, or $9.99 once for up to five Macs. No subscription, no per-image fees, no monthly cap once you have a license. Over a single year of moderate usage (say 5,000 images), TinyPNG's API costs $300+ and Kompressor costs $2.99. The math is brutal; the trade-off is that Kompressor is desktop only and TinyPNG fits inside server pipelines.
You compress images on a Mac as part of real desktop work — websites, social media, email, newsletters.
You care about privacy and don't want your client mockups or personal photos uploaded to a third-party server.
You hit TinyPNG's 5 MB or 20-image limits regularly and want to drop whole folders without thinking.
You sometimes need to compress offline — on a plane, in a tunnel, in a meeting room with no Wi-Fi.
You need an API or WordPress plugin for server-side or CMS-driven compression workflows.
You are not on a Mac, or you want zero install for a one-off compression job.
You compress fewer than 20 small images per batch and don't mind the upload.
10 images every day, no email, no card, no upload. Compress a folder, see what you've been missing.
macOS 11+ · 6 MB universal binary · refundable within 14 days
Yes. TinyPNG is a web service — when you drop an image on their site, it is uploaded to their servers, compressed, and a smaller copy is sent back. Kompressor processes everything locally on your Mac. No upload, no internet needed.
On JPEG and WebP, file size and visual quality are within a few percent of each other. TinyPNG has a slight edge on PNG quantisation in some cases. For 95 percent of practical use the difference is invisible at normal viewing distance.
Yes. TinyPNG caps the free web upload at 20 images per batch and 5 MB per file. Kompressor has no batch cap and no per-file size limit — drop a folder of 500 photos and it processes them all in one go.
Yes, fully. Kompressor needs no internet. You can compress on a plane, in a tunnel, with the Wi-Fi unplugged. TinyPNG requires an active internet connection because the work happens on their servers.
For desktop use on a Mac — yes, in most cases. For automated CMS pipelines (WordPress, Photoshop plugins) TinyPNG's API and plugins still have an edge. The two can also coexist: Kompressor for desktop, TinyPNG API for server-side.