Free alternative to TinyPNG
Looking for a free alternative to TinyPNG that does not upload your images? Tools Nimbus is a free, no-signup developer toolkit that runs entirely in your browser, so your data is never uploaded to a server. The Image Compressor shrinks JPG and PNG files locally with a quality slider, has no 20-image batch limit and no 5 MB file cap, and keeps working offline once the page has loaded.
Last updated June 2026
The short version
TinyPNG is a genuinely good tool, and the honest pitch is not that it costs money or steals your data, because for casual use it is free and its privacy policy is clear. The real distinction is architecture: TinyPNG uploads every image to its servers to run its compression, while the Tools Nimbus Image Compressor does all the work inside your browser tab. Pick Tools Nimbus when you want no uploads, no account, and no batch or size limits for compressing photos and JPGs. Pick TinyPNG when you specifically need its stronger PNG compression, transparency-preserving output, or WebP and AVIF export.
Feature comparison
The table compares the free web versions of each tool. A capability marked Yes is present, No is absent, and Partial exists with a caveat. Pricing is marked as of 2026.
| Capability | Tools Nimbus | TinyPNG (web) |
|---|---|---|
| Price (as of 2026) | Free, $0 | Free for casual use; Pro about $39/year |
| Account or signup required | No | No (web tool); account needed for Pro and API |
| Images processed in your browser | Yes | No (uploaded to TinyPNG servers) |
| Files never uploaded to a server | Yes | No |
| Per-batch image limit | None | 20 images per session |
| Per-file size cap | None (limited by browser memory) | 5 MB per file |
| Keeps working offline after first load | Yes | No (server-side compression) |
| Adjustable quality slider | Yes | Partial (automatic; manual control via API) |
| Preserves PNG format and transparency | No (output is JPEG) | Yes |
| Smart lossy PNG quantization | No | Yes |
| WebP and AVIF output | No | Yes |
| Developer API for automation | No | Yes (Tinify API) |
Where Tools Nimbus is genuinely different
TinyPNG is free for casual use and does not sell your data, so the easy marketing lines do not apply. The verifiable differences come down to how and where the compression runs.
- No uploads. TinyPNG sends each image to its servers to compress it. The Tools Nimbus Image Compressor uses the browser Canvas API, so the file is read, compressed, and downloaded without ever touching a server. There is no upload endpoint to send it to.
- No batch or size limits.The free TinyPNG web interface caps you at 20 images per session and 5 MB per file. Tools Nimbus has no per-batch count and no fixed size cap; the practical ceiling is your device's memory.
- Works offline. Because all logic ships to the browser, you can reopen the tab and keep compressing with no connection. TinyPNG needs the network because the compression happens server-side.
Where TinyPNG is still the better pick
A fair comparison cuts both ways. TinyPNG's server-side engine does things a Canvas-based tool cannot, and if you need any of these, TinyPNG (or an open-source option like Squoosh) is the right call:
- PNG transparency. Tools Nimbus outputs JPEG, which has no alpha channel, so a transparent PNG becomes a flat image. TinyPNG keeps PNGs as PNGs and preserves transparency.
- Stronger PNG compression.TinyPNG's smart lossy quantization usually yields smaller PNGs at a given quality than a plain re-encode.
- Modern formats and automation. TinyPNG can output WebP and AVIF and offers the Tinify API for build pipelines. Tools Nimbus is a manual, in-browser tool.
How to compress an image with Tools Nimbus
Open the Image Compressor, drag in a JPG or PNG, and it compresses instantly. Drag the quality slider to trade size against fidelity and watch the before and after byte counts update live, then download the result. For photos and JPGs the JPEG output is usually smaller than the original at a quality you cannot see degrade. Nothing you drop in is uploaded anywhere.
Related browser-based tools
Images rarely travel alone. If you are embedding a small icon directly in CSS or HTML, the Base64 Encoder and Decoder turns a file into a UTF-8-safe data URI, and the Color Palette Generator helps you build a matching palette around an image. For more browser-based utilities, see the guides index. Everything runs locally, so your data never leaves your device.