LagLight

Best GlassWire Alternatives & Free Tools to See What's Using Your PC

· 7 min read

Quick answer: You probably don't need to install anything. Task Manager and Resource Monitor are already on your PC and cover most needs for free. If you want a friendlier or more detailed view, GlassWire (freemium) is the most polished, Portmaster is a capable free/open-source pick, and Microsoft's free Sysinternals tools (TCPView, Process Monitor) show the deepest detail. Below is an honest rundown — and yes, every link here goes to the tool's official site. We take no commission on any of these.
Why you can trust this list: LagLight makes no money from these recommendations (no affiliate codes, no kickbacks). We're a free resource. We tell you what each tool actually does, what it costs, and where it falls short — then point you to the official download so you're never on a sketchy mirror site.

Start here: already on your PC (free)

Task Manager

Cost: Free, built into Windows · Shows: CPU, memory, disk, and network use per program

Press Ctrl + Shift + Esc. Sort by the Disk or Network column to instantly see what's busiest. For 90% of "what's slowing my PC" questions, this is enough. No install, no risk.

Resource Monitor (resmon)

Cost: Free, built into Windows · Shows: the exact files and network connections each process is using

Press Win + R, type resmon. The Disk tab shows the actual files being read/written; the Network tab shows remote connections. More detail than Task Manager, a little busier to read. Still no install.

Free, official downloads (when you want more)

Portmaster

Cost: Free, open source · Shows: per-app network connections, with optional firewall rules

A genuinely free, open-source way to see every app's network activity and block the ones you don't want phoning home. The closest thing to a no-cost, no-strings network monitor. Slightly technical but well-documented.

Official site: safing.io →

Sysinternals TCPView & Process Monitor (by Microsoft)

Cost: Free · Shows: every active network connection (TCPView) or every file/registry access (Process Monitor)

Powerful, official Microsoft tools. TCPView maps network connections to the programs making them. Process Monitor captures all file activity — be warned, it's a firehose of detail, best for tracking down a specific mystery process.

Official site: Microsoft Sysinternals →

Wireshark

Cost: Free, open source · Shows: raw packet-level network traffic

The industry standard for deep network analysis. Overkill for most gamers and quite technical, but unmatched if you genuinely need to inspect traffic at the packet level.

Official site: wireshark.org →

The polished all-in-one (freemium)

GlassWire

Cost: Freemium — free tier limited; Premium ~$36/yr · Shows: network + disk, CPU, memory, GPU monitoring, with graphs and alerts

The most beginner-friendly option with a clean visual timeline. Note: today's GlassWire is broader than "network only" — it also monitors disk, CPU, memory, and GPU per app. The free tier includes short history and a basic "Click-to-Block" with limits; advanced modes (Ask to Connect, Lockdown, profiles, bidirectional control) are Premium. Their "53 million downloads" figure is a vendor claim, not independently audited.

Official site: glasswire.com →

If you want to limit or prioritize apps

NetLimiter

Cost: Paid · Does: set per-app bandwidth limits and priorities

If you need to cap a specific app's bandwidth (or give your game priority), NetLimiter is the established tool. Paid, aimed at power users.

Official site: netlimiter.com →

NetBalancer

Cost: 14-day free trial, then $49.95 (one PC, lifetime) · Does: per-app bandwidth priorities and limits

A paid alternative to NetLimiter for prioritizing which apps get bandwidth. It offers a 14-day full trial, after which it's a one-time $49.95 lifetime license for one PC (one year of updates and services). There's no permanent free tier.

Official site: netbalancer.com →

Razer Cortex (Game Booster & System Booster)

Cost: Free · Does: manages background apps when a game starts, and removes selected junk files

A free suite with two separate features: Game Booster temporarily stops or manages non-essential apps when a game launches, and System Booster separately removes selected junk files. Some gamers find Game Booster helps; others feel it makes little difference or dislike booster-style tools. It's a blunt instrument, not a diagnostic.

Official site: razer.com/cortex →

Which should you actually use?

Confused about why something is busy in the first place? That's what our guides are for — start with why is my internet so slow? or 100% disk usage.

Frequently asked questions

Is there a free alternative to GlassWire?
Yes. Task Manager and Resource Monitor are free and built into Windows. Portmaster is a free, open-source network monitor. GlassWire itself has a limited free tier.
Are these recommendations affiliate links?
No. LagLight takes no commission. Every link goes to the tool's official website so you avoid unofficial download mirrors.