− “Just a small refactor.” + Famous last words.

A fast desktop tool for comparing files, folder trees, Git refs, and GitHub pull requests, side by side or unified, with syntax highlighting that stays smooth on enormous diffs.

Download Diffly
View source
Diffly src › diff › engine.ts Modified
+5 −3 · 5 files changed

Click any file, or switch Split / Unified.

Features

Everything you need to read a diff.

Compare whole folder trees

Point Diffly at two directories and walk every changed entry in a real tree. Files open one at a time while the rest stream into a background cache.

Diff straight from Git

Compare your working tree, a ref range, or a single commit of any local repository.

Paste a GitHub URL

Open pull requests and compare URLs directly, .diff/.patch links and fork refs included.

Ignore the noise

Compare while ignoring whitespace or case, so only the changes that matter show up.

Split & unified views

Switch between side by side and inline at a keystroke. Panes stay synced as you scroll.

Highlighted & themeable

Shiki-powered syntax highlighting across many languages, in light or dark, with a built-in theme editor.

Picks up where you left off

Your compare session persists locally, so a restart never loses your place.

Updates from GitHub

Update checks run against GitHub releases; you decide when to install.

v0.2.3 available · ready to install

Performance

Built to stay smooth when diffs get big.

Large text diffs and sprawling directory trees render through virtualization, so scrolling stays fluid and the UI never blocks while results stream in.

  • Virtual rendering for large text diffs and directory trees
  • Bounded background preloading, no runaway memory
  • Scroll anchoring and synced panes that don't jump
  • Fails closed and visibly, so your state is never silently lost
engine.ts 14,302 lines
Textvirtualized diffs
Treeshuge directories
Cacheloads in background

Your code never leaves your machine.

Diffly is a local desktop app. No accounts, no telemetry, no uploading files to a server to compare them. Everything runs on your hardware, exactly how diffing sensitive code should work.

Download Diffly

The latest release, v0.2.3. Free, open source, ready in seconds on Windows, macOS, and Linux.

Download v0.2.3 (.exe)
All releases
  • Windows, macOS & Linux
  • GPL-3.0, open source
  • Update checks built in