TinyPNG Alternative: Unlimited Compression That Never Uploads Your Files

You drag 40 product shots onto TinyPNG. It takes the first 20. Then it hands back the 8 MB hero image your photographer sent, because the free web tool will not accept anything over 5 MB.

So you split the batch. Wait for the upload. Do it again. That is usually the exact moment somebody types "TinyPNG alternative" into Google.

TinyPNG is a good product, and it deserves credit for making PNG quantization a normal thing that normal people do. But the free tier has a fixed shape, and once your work outgrows that shape you either pay or you go looking.

There is a second reason people look around, and it has nothing to do with limits. Every file you drop into TinyPNG is uploaded to their servers, compressed there, and sent back to you. For a blog header, nobody cares. For a scanned contract, a passport photo, or an unreleased product render, it is a different conversation.

What ZeroPNG does differently

ZeroPNG compresses images inside your browser tab. Nothing gets uploaded. The compression engines are compiled to WebAssembly, which is just a way of running fast, low-level code directly in a web page. Your own laptop does the work that TinyPNG's server would have done.

Two useful things fall out of that. There is no upload wait, so a 300-image batch starts compressing the second you drop it. And there is no per-user server cost for us to recover, which is why there is no 20-file cap and no paid tier to graduate into.

You do not have to take our word for it. Open the Image Compressor, turn off your Wi-Fi, and compress something. It still works. Or open the Network tab in your browser dev tools and watch it stay empty while you work.

TinyPNG vs ZeroPNG, as of August 2026

Prices and limits change. These are taken from TinyPNG's own site in August 2026, so check theirs before you buy anything.

Feature	ZeroPNG	TinyPNG (free web tool)
Where it runs	Your browser	TinyPNG's servers
Files uploaded	None	Every file
Images per batch	No cap	20 per session
Max file size	20 MB	5 MB
Format conversions	No cap	3 per session
Output formats	PNG, JPG, WebP, AVIF	AVIF, WebP, PNG, JPEG
Account needed	No	Yes, for paid plans
Works offline	Yes, after the first visit	No
Developer API	None	Yes, 500 free compressions a month
Paid tiers	None	Web Pro and Web Ultra, billed yearly

A few things worth pulling out of that table. TinyPNG's paid Web Pro plan, $39 per licence per year, lifts the file cap to 75 MB and removes the compression limit, but it still allows only 3 format conversions per session. Unlimited conversion is a Web Ultra feature, at $149 per licence per year, which also takes the file cap to 150 MB. Both are yearly per-user subscriptions. Prices move, so confirm them on their pricing page before you buy.

Their Developer API pricing is public and clear: the first 500 compressions each month are free, then $0.009 per compression up to 10,000, then $0.002 above that. Credit bundles are sold separately and do not expire.

One correction to a claim you will see everywhere

Plenty of articles still say TinyPNG allows 20 images per month. It does not, and it has not for a while. Their own site describes the free tier as up to 20 images at once, each up to 5 MB, and their pricing page lists that 20 as a per-session limit. Those are completely different things. Start a fresh session and you get another 20. If your work is occasional and small, that is genuinely workable and you may not need an alternative at all.

Where it stops working is the shape of real batches. Product catalogues, event galleries and blog archives do not arrive in groups of 20, and splitting a 340-file folder into 17 sessions is the kind of task people quietly abandon halfway through.

Does the output actually look the same?

For PNG, mostly yes, because both tools are doing the same thing. TinyPNG built its reputation on color quantization: a 24-bit PNG with millions of colors gets reduced to a palette of 256 or fewer, chosen carefully enough that your eye does not notice. That is where the dramatic 60 to 80 percent reductions come from. ZeroPNG applies the same technique in the browser using UPNG.js.

For JPEG and WebP the philosophies differ. TinyPNG picks a quality level for you and returns one result. ZeroPNG hands you the slider. If you have ever looked at a TinyPNG result and thought "that is more compression than I wanted on a portrait," the slider is the answer to that complaint.

The one place we would not argue is consistency. An automatic algorithm applied to 500 mixed images will produce more even results than a human picking one number for all of them. If you want a single setting that is right for every file, TinyPNG's automatic mode is a reasonable thing to want.

Where TinyPNG is still the better choice

This is the part most comparison pages skip. There are real situations where TinyPNG wins and ZeroPNG cannot compete, and pretending otherwise would waste your time.

You need compression inside a build pipeline

ZeroPNG has no API. It cannot have one. There is no server doing the compressing, so there is nothing for your CI job to call. If you want images optimized automatically during a deploy, inside a Node script, or in a Laravel upload handler, TinyPNG's API is built for exactly that and ZeroPNG is the wrong tool. Not "a bit worse". Wrong.

You want WordPress to compress on upload

TinyPNG ships an official WordPress plugin that compresses images as they are uploaded to the media library. That is a discipline problem solved with software. With ZeroPNG you have to remember to compress before you upload, and if your site has five authors, some of them will forget. On a multi-author site, the plugin is worth the money.

You live inside Figma, or you need a CDN

TinyPNG has an official Figma plugin for exporting and compressing designs in one step, plus a hosted image CDN that optimizes and serves images automatically. ZeroPNG has neither. One correction while we are here: TinyPNG's Photoshop plugin has been deprecated and is only supported up to Photoshop CC 2023, so do not pick TinyPNG for that reason specifically.

You work with genuinely enormous files

ZeroPNG's compressor rejects anything over 20 MB. That is our limit, not theirs, and it exists because a browser tab that tries to decode a 100 MB TIFF will usually just crash. TinyPNG's Web Ultra plan accepts 150 MB per image. If you handle giant scans or stitched panoramas, that gap is real.

How to switch

There is nothing to migrate, which is the nice part about tools with no accounts.

1. Open the ZeroPNG Image Compressor.
2. Drop in your whole folder. All of it. There is no 20-file ceiling to work around.
3. Pick an output format, or leave it on the original. Quality at 75 to 80 is the sweet spot for photos.
4. Hit compress, then download everything as one ZIP.

If you also need format conversion, the Image Converter handles PNG, JPG, WebP and AVIF with no per-session conversion limit, and there are dedicated AVIF and JPEG XL converters if you want those specifically. Working with iPhone photos, use the HEIC Converter first.

Common questions

Is ZeroPNG's compression quality as good as TinyPNG's?

For PNG, they use the same underlying technique. TinyPNG built its reputation on color quantization, which reduces a 24-bit PNG down to a smaller palette. ZeroPNG uses UPNG.js to do the same thing in your browser. Results land in the same range. For JPEG and WebP, ZeroPNG gives you a quality slider so you decide the trade-off, while TinyPNG picks a setting for you automatically.

Why does TinyPNG limit free users when ZeroPNG does not?

Because TinyPNG pays for the CPU time. Every free compression costs them server resources, so a cap is a rational business decision. ZeroPNG uses your computer's CPU, so an extra 500 images costs us nothing.

Can ZeroPNG replace the TinyPNG WordPress plugin?

Not automatically. The plugin compresses on upload without anyone thinking about it. ZeroPNG is a manual step you take before uploading. For a solo blog that is fine. For a team, the plugin is more reliable.

Does ZeroPNG have a compression API?

No, and it cannot have one. There is no server-side image processing here, so there is nothing for a build script to call. If you need compression inside a CI pipeline or a deploy step, the TinyPNG developer API is the right tool for that job.