I’ve been messing with website performance for a while now. And one thing that kept coming up? Image sizes. Big images slow everything down. Visitors bounce. Google notices. It’s a whole thing.
So I started looking into WebP. If you haven’t heard of it, it’s an image format Google cooked up. The idea is simple: smaller files, same-looking pictures. Lossy WebP images are about 25-34% smaller than JPEGs at the same quality. Lossless? 26% smaller than PNGs. That’s not nothing.
But here’s the annoying part. Most online converters have limits. Convert five images and suddenly they want your credit card. Or they drown you in ads. Or they watermark your stuff. I got tired of it.
Turns out, Google already gave us the answer. For free. No limits. No ads. Just a command line tool that does exactly what it says.
I’m on a MacBook, so I’ll walk you through what I did. If you’re on Windows or Linux, the tool works too — the setup is just a little different.
What Actually Is WebP?
Before we get into the how, let’s talk about the what.
WebP supports both lossy and lossless compression. It also handles transparency and animation. Think of it as JPEG, PNG, and GIF all rolled into one format — but smaller.
The browser support is basically universal at this point. Chrome, Firefox, Safari, Edge — they all handle WebP natively. As of 2026, over 97% of global web traffic comes from browsers that support it. The only real holdout is Internet Explorer, and honestly? If you’re still supporting IE, you have bigger problems.
So why isn’t everyone using it? Laziness, mostly. And the hassle of converting.
The Problem With Online Converters
I tried a bunch of them. Free ones, paid ones, ones that pretended to be free until you hit your fifth image.
Most of them work fine for a single image. But if you have a folder full of product photos or blog images? Good luck. You either pay up, sit through a million ads, or deal with some sketchy watermark.
I actually covered something similar before — Google Lets You Remove AI Watermarks (Invisible Ones Stay). That one was about watermarks too, but a different kind. Same vibe though: Google gives you the tools, you just have to know where to look.
Anyway, back to WebP.
The Free Way: Google’s Own Tool
Google open-sourced the whole WebP thing. The tools are right there on their developers site. No catch. No “free trial” nonsense.
The tool is called cwebp. It’s a command-line encoder that takes JPEG, PNG, or TIFF and spits out WebP. It’s been around for years. It’s stable. It just works.
I use a Mac, so I went the Homebrew route. Here’s exactly what I did.
Step-by-Step: Setting It Up on a Mac
First, open Terminal. If you’ve never used it before, don’t panic. It’s just a text window where you type commands.
Step 1: Install Homebrew
Homebrew is a package manager for macOS. Think of it as an app store for command-line tools. Paste this in and hit enter:
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"Fair warning: this requires a VPN or proxy if you’re in certain regions. The script pulls from GitHub and other sites that might be blocked. I learned this the hard way.
Step 2: Install the WebP tools
Once Homebrew is set up, this part is easy:
brew install webpThat’s it. Homebrew grabs the package and installs everything you need.
Step 3: Convert your first image
Now the fun part. Let’s say you have an image called 1.jpg sitting in your Downloads folder. To convert it, type:
cwebp ~/Downloads/1.jpg -o ~/Downloads/1.webpThe -o flag tells it where to save the output. Hit enter and boom — you’ve got a WebP file.
Wait, I should have mentioned this earlier — you can also adjust the quality. Add -q 80 for 80% quality. The default is 75, which is usually fine. Higher number = better quality = bigger file. Play around with it.
What About Batch Conversion?
Here’s where it gets really useful.
If you have a whole folder of images, you don’t want to run that command one by one. I didn’t. So I found a workaround.
You can use a loop. In Terminal, navigate to your folder:
cd ~/Downloads/images/Then run this:
for i in *.jpg; do cwebp "$i" -o "${i%.jpg}.webp"; doneThis grabs every JPG in that folder and converts it to WebP, keeping the same filename. Change *.jpg to *.png if you’re working with PNGs.
Took me about 30 seconds to convert 50 product photos. Normally that would take forever with an online tool.
One Thing That Tripped Me Up
The first time I tried this, I forgot to install Homebrew first. I just typed brew install webp and got a “command not found” error. Obvious in hindsight.
Also, the cwebp command is case-sensitive. I typed Cwebp once and it didn’t work. Small thing, but annoying.
Oh, and if you’re on an M-series Mac (M1, M2, M3), the precompiled binaries work fine. No extra steps needed.
Is It Worth the Effort?
Honestly? Yeah.
If you run a website, switching to WebP is one of the easiest performance wins you can get. It’s free. It’s supported everywhere. And the file size savings are real.
I’m not saying you need to convert every single image you’ve ever made. But for new stuff? Absolutely. Make it a habit.
The command-line approach isn’t for everyone. If you hate typing commands, there are GUI tools that use the same underlying cwebp engine. But they’re just wrappers. The real magic is the free, unlimited, no-ads tool that Google already gave us.
Skip the online converters. Skip the paid tools. Open your terminal and give cwebp a shot.
I’ll keep using it and see how it goes. But so far? Solid.
