~100 KB
Single exe
The antivirus that
stays calm.
Harbor is a small, friendly antivirus for Windows. Signature scanning, heuristics, real-time protection and a safe quarantine — in a quiet little app with no ads, no popups and no "your PC is at risk!" scare tactics.
<1s
Cold start
SHA-256
Signature engine
0
Trackers & ads
Everything an antivirus needs — nothing it doesn't
Small app, real protection
Not a toy, not bloatware. A focused scanner that does its job, tells you the truth, and stays out of your way.
Signature scanning
Every file is hashed with SHA-256 and checked against a plain-text signature database. Update it with one click from Settings — no hidden downloads.
Heuristics
Catches common tricks without a signature — double extensions like invoice.pdf.exe, packed executables hiding in temp folders, hidden system files where they don't belong.
Real-time protection
Watches the folders you choose — Downloads and Desktop by default — and scans new files the moment they appear. Known threats are quarantined automatically.
Safe quarantine
Flagged files are neutralized, never silently deleted. One click restores anything flagged by mistake — byte-for-byte identical. Your files, your call.
Quick, full or custom scans
Scan the usual suspects in seconds, every drive when you're feeling thorough, or any single folder you pick. Cancel any time, exclude anything.
Plain settings
Exclusions, size limits, startup behavior, signature updates. One readable settings file in %AppData%\Harbor — delete it and Harbor forgets you.
Harbor vs the usual suspects
Why people switch
Most free antivirus products are louder than the malware. Harbor takes the opposite approach.
| Harbor | Typical free antivirus | |
|---|---|---|
| Install size | ~100 KB | 500 MB+ |
| Ads & upsell popups | None, ever | Constant |
| "Your PC is at risk!" scare screens | Never | Daily |
| Telemetry & data collection | Zero — nothing leaves your PC | Extensive |
| Browser toolbars & "extras" | None | Bundled |
| Quarantine with honest restore | ✓ | Varies |
| Open source | ✓ MIT | ✗ |
| Price | Free, actually free | "Free" |
Get started in a minute
Install Harbor
Grab the installer, or build it yourself from source — it compiles with tools already on every Windows PC.
Download Recommended
- Grab the latest release from GitHub — installer or portable zip.
- Run it — if SmartScreen appears, click More info → Run anyway (Harbor is new and unsigned, the source is right here to check).
- Open Harbor, flip on real-time protection, run your first quick scan.
Build from source
No SDK, no Visual Studio — Harbor builds with the C# compiler that ships inside Windows.
# Clone and build (any Windows 10/11 PC)
git clone https://github.com/AverageCodeNerd/harbor.git
cd harbor
powershell -ExecutionPolicy Bypass -File build.ps1
# Run the engine tests
powershell -ExecutionPolicy Bypass -File tests\run-tests.ps1
git clone https://github.com/AverageCodeNerd/harbor.git
cd harbor
powershell -ExecutionPolicy Bypass -File build.ps1
# Run the engine tests
powershell -ExecutionPolicy Bypass -File tests\run-tests.ps1
Windows 10 & 11
.NET Framework 4.8 (built in)
No runtime downloads
~100 KB result
Try it safely
Test the detection — without real malware
Create a text file containing exactly this line and scan its folder. Harbor flags it as Harbor-Test-File (not a virus):
Honest note: Harbor is a lightweight companion scanner, not a replacement for Windows Defender — the two run happily side by side. A kernel-mode driver for deeper protection is on the roadmap.
Calm down your antivirus
Free, open source, and smaller than a photo. Your files stay yours, your PC stays quiet.