the origin story
I got tired of
doing it manually.
Converting images one by one is genuinely one of the worst tasks in web dev. So I built Leano — a tool (actually three tools) that batch converts your entire folder of JPGs and PNGs to WebP or AVIF. Locally. No uploads. No waiting.
80%+
typical size reduction
100%
runs locally, no uploads
WebP + AVIF
modern format support
okay but why though
Images are almost always the heaviest thing on a webpage. We're talking JPEGs and PNGs that are 10x larger than they need to be. WebP and AVIF cut that by 70–90% — same quality, fraction of the size. Your site loads faster, your Lighthouse score goes up, users don't bounce.
The problem is converting them is annoying. Every tool either makes you upload to some random server (weird), handles one file at a time (unacceptable), or completely destroys your folder structure (criminal). Leano does none of that. It runs in your browser or terminal, handles whole directories in one shot, and keeps your file layout exactly as-is.
three ways to use it
Web App
Drop a folder, pick a format, click convert. Everything runs in your browser — nothing touches a server. Genuinely zero effort.
CLI
One command and your whole directory is done. Plug it into your build script and never think about it again.
VS Code & Cursor
Right-click images or folders in the Explorer, or run from the command palette — same CLI, fully local inside your editor.
GitHub Workflow
A GitHub Action that auto-optimizes images in every PR. Basically set it up once and let the bot do the work while you nap.