PortFinder identifies which switch, switchport, and VLAN your machine is currently plugged into by listening for the discovery packets the switch is already broadcasting. No agent on the switch, no SNMP, no login — just a passive 30-second listen on the wire.
Ships a desktop GUI and a headless CLI in one binary. The CLI takes portfinder capture --interface <NIC> --protocol LLDP [--json]. Requires Npcap (with "Allow non-administrators to capture" enabled) for non-administrator capture.
What's new in 4.2.0
What's Changed - release: prep v4.2.0 (9876cc5) - release: prep v4.2.0-beta.1 (ea01d17) - test(capture): name the parser fn type (clippy::type_complexity) (fca56cc) - docs(todo): tick off the gpui pin and the parser no-panic test (0a99242) - style: cargo fmt the crate; check formatting in CI (279628a) - test(capture): parsers never panic on random or truncated frames (09bf585) - refactor(ui): history, settings rows and result copy on GPUI Kit (6f05942) - build(deps): move to GPUI Kit 0.8.0 (gpui-pre 0.3.9) (0a2b521) - fix(docs): refresh docs-next toolchain — clears all 32 advisories (5ebd49e) - chore(dependabot): point at the 4.x layout and group updates (49d099d) - fix(deps): patch rustls, h2, tokio, crossbeam-epoch and friends; add cargo-deny (2b84709) - build(deps): bump actions/download-artifact from 8.0.1 to 8.0.2 (7b634cd) - build(deps): bump vedantmgoyal9/winget-releaser (a77832b) - build(deps): bump taiki-e/install-action from 2.85.5 to 2.87.26 (b4daac3) - build(deps): bump softprops/action-gh-release from 3.0.2 to 3.0.3 (5c3e08f) - build(deps): bump Swatinem/rust-cache (5a293de) - fix(appimage): AppRun runnable by every user, not just root (03db90e) - deps: clear all open Dependabot alerts (ced3471) - build(deps): bump taiki-e/install-action from 2.83.2 to 2.85.5 (0b1dbd3) - build(deps): bump vedantmgoyal9/winget-releaser (ce0b030) - build(deps): bump actions/checkout from 7.0.0 to 7.0.1 (4fcb6af) - build(deps): bump actions/setup-node from 6 to 7 (ebcb1cb) - build(deps): bump softprops/action-gh-release from 3.0.1 to 3.0.2 (91f8cfa) - docs(winget): CI hookup is live — workflow_run auto-submission (24738da) - after_release: fix dead trigger — release event never fires (ef60ab3) Full Changelog: v4.1.4...v4.2.0
What's Changed - Bump to 4.1.4 (86d3eed) - deps: bump gpui/gpui-component past async-tar CVE + wrap long tooltips (#65) (c5ed6af) - build(deps): bump actions/cache from 5 to 6 (#60) (fde733a) - build(deps): bump taiki-e/install-action from 2.82.2 to 2.83.2 (#63) (9b2c968) - docs: lifecycle screenshots + top-right nav pills (#64) (f54b491) - docs(deps): override js-yaml + esbuild past CVE-affected versions (bc9c666) - build(deps): bump astro from 6.2.1 to 6.4.6 in /docs-next (#56) (455b015) - build(deps): bump vedantmgoyal9/winget-releaser (#53) (c2e4a8d) - build(deps): bump actions/checkout from 6 to 7 (#57) (4deca53) - build(deps): bump softprops/action-gh-release from 3.0.0 to 3.0.1 (#58) (28755b8) - build(deps): bump taiki-e/install-action from 2.79.0 to 2.82.2 (#59) (45b78bf) - readme: note the Homebrew 6.0.0 tap-trust step (a2d02f7) Full Changelog: v4.1.3...v4.1.4
4.1.3Jun 3, 2026
What's Changed - release: prep v4.1.3 (3bad1f3) - release: prep v4.1.3-beta.1 (6aa5e85) - fix(gui): grow window to fit settings popover when it opens (cdef868) - docs(site): add "← packetThrower" back-link to top nav (4ad1b4a) - docs(install): surface winget availability across README + docs (df2138f) - build(ci): automate winget submissions via after_release.yml (5910024) - revert: roll back v4.1.3-beta.1 (Hyprland resize work) (3794854) - release: prep v4.1.3-beta.1 (ac53572) - fix(linux): drop per-frame window.resize loop that races wlroots popups (bd399c6) - packaging: render v4.1.2 winget manifests for upstream PR (799440e) Full Changelog: v4.1.2...v4.1.3
4.1.2May 20, 2026
Frequently asked questions
Is PortFinder free?
Yes. PortFinder is free and open-source software released under the GPL-3.0 license.
What is the latest version of PortFinder?
The latest version is 4.2.0, released on Oct 26, 2026.
Is it safe to download PortFinder?
The download button links to the official installer published on github.com, the same file Windows Package Manager installs. You can verify the downloaded file by comparing its SHA-256 checksum with 9cdd22b59d0e51b1dee3024ada812b0c3fe07f11d859ade591c0417d5e8aeb34.
Which Windows versions does PortFinder support?
PortFinder runs on Windows and is available for 64-bit (x64), ARM64 systems.
How do I install PortFinder silently?
Run the offline installer with msiexec /i "PortFinder_4.2.0_amd64_en-US.msi" /quiet /norestart, or install it with Windows Package Manager: winget install --id=packetThrower.PortFinder -e --silent.
How do I uninstall PortFinder?
Open Settings › Apps › Installed apps, find PortFinder and select Uninstall. From the command line, run winget uninstall --id=packetThrower.PortFinder -e.
Alternatives to PortFinder
Other Networking programs for Windows from different developers.
