I compress images for websites, side projects, and client work. For years that meant TinyPNG or Squoosh. Neither matched how I actually work.
TinyPNG is fast and familiar. It also wants the file. You upload. The free web tool caps you at 20 images per session and 5 MB each. After that you pay, wait, or split a folder into batches of twenty. The compression is fine. The trust model is “someone else’s server, hope they delete it.” I did not want that for client photos, UI screenshots, or anything I would not put on a public CDN first.
Squoosh is the other extreme, and I still use it for one picture. Drop a file, pick MozJPEG / WebP / AVIF / JXL / Oxipng, compare sides, download. The image never leaves the browser. That part is right. The workflow is not: one file at a time, no folder drop, no ZIP, no “make this under 100 KB.” The CLI and library were deprecated years ago. The web app still works; it is not where I go when a public/images folder lands on my desk.
I am Mehdi Tareghi. I build software from Iran. I got tired of the gap and built Asset Melt: Squoosh-grade WASM codecs, plus the batch and budget pieces I kept missing.
What it does
Studio is a static app. Open it, drop files, encode on your machine, download. No account.
Codecs run in Web Workers via WebAssembly: MozJPEG, AVIF, WebP, Oxipng, and JPEG XL (plus QOI). HEIC from a camera roll decodes locally with libheif. PNG is lossless Oxipng by default, with optional palette reduction when you want lossy PNG-8.
The parts I built because Squoosh would not:
-
Batch and folders. Drop a directory. Nested images are walked; non-images are skipped. The queue is reorderable. You can add files while a batch is encoding, pause mid-run, and export a ZIP that keeps relative paths (
products/a/hero.webp). There is no 20-image cap. Device memory is the cap. - A KB budget. “Quality 75” is not a size. I often need under 50 KB, under 100 KB, or under 200 KB for an OG image, a newsletter hero, or a card. Studio binary-searches quality (and PNG palette size) against that cap for JPEG, WebP, AVIF, and JXL.
- Platform kits. Fit-to-size presets for OG, X, Instagram, YouTube, favicon, App Store screenshots, and newsletter widths — as ZIPs, not a scavenger hunt through a resize panel.
You can also export more than one format in a single run (AVIF / WebP / optional JPEG). Recipes live in the URL (?recipe=); photos do not. Code is at github.com/mehditareghi/assetmelt.
Images stay on the device. The site is not invisible.
Image bytes never upload. There is no image API. I cannot see, store, or recover your files. Close the tab and in-progress work is gone unless you exported. That is architecture, not a footer promise.
The site still has UI analytics. I use Google Analytics 4 for page views and coarse events (files added, processing finished, export — counts and formats, not filenames or pixels). Sentry gets crashes, traces, and sampled session replay of the website chrome, not your pictures: media is blocked, Studio previews are local blob URLs. Vercel records web vitals. It is all on assetmelt.com/privacy. If a privacy pitch hides telemetry, it is a lie. This one does not.
Try it in about 20 seconds
- Open assetmelt.com/studio. No signup.
- Drop a JPEG, a PNG, or a whole folder.
- Pick WebP or AVIF, or turn on a size budget — under 100 KB is a good first test.
- Process (Cmd/Ctrl+Enter).
- Download the file, or ZIP the queue.
If you already know the cap, these open Studio with the budget on: under 50 KB, under 100 KB, under 200 KB.
First load pulls WASM modules. After that, work is local CPU. A cheap laptop will feel a large AVIF batch. That is expected.
Squoosh vs TinyPNG vs Asset Melt
Features only. No invented traffic numbers, no “X% smaller” claims.
| Squoosh | TinyPNG (free web) | Asset Melt | |
|---|---|---|---|
| Where encoding runs | Your browser (WASM) | Tinify’s servers (upload) | Your browser (WASM) |
| Account | No | Not required for the free web tool | No |
| Batch | One image at a time | Up to 20 images / session, 5 MB each | Folder drop, queue, ZIP; RAM is the limit |
| Hit a KB target | Quality / codec sliders | Automatic compression, no “under N KB” budget | Binary-search under 50 / 100 / 200 KB |
| Codecs / formats | MozJPEG, WebP, AVIF, JXL, Oxipng, QOI, WP2 | JPEG, PNG, WebP, AVIF | MozJPEG, WebP, AVIF, Oxipng, JXL, QOI; HEIC decode |
| Platform kits (OG, X, App Store, …) | No | Resize via paid / API, not kit ZIPs | Yes |
| Open source | Yes | No | Yes |
| Images uploaded | No | Yes | No |
| Site analytics | Yes (Google Analytics on the app) | Yes (it is a hosted service) | Yes — UI only, disclosed on /privacy
|
TinyPNG is still the right choice if you want a hosted API, a WordPress plugin, or you are fine uploading and staying inside the free 20. Squoosh is still the right choice if you want a side-by-side codec lab for one file. I use both as references. I built Asset Melt for the days I have a folder, a size cap, and no reason to send pixels off-device.
I did not write MozJPEG. I wired the same family of engines Squoosh proved in the browser (@jsquash, libheif) into a React app, then added a queue, a budget search, and the export paths I kept wishing existed. There is no cloud history and no team workspace — there is no backend that receives photos. It is free. No plan page.
If that is the workflow you already have in your head — batch, a KB number, files that stay put — open the studio and drop something.
