iperf3 vs M-Lab NDT
iperf3
software.es.netM-Lab NDT
measurementlab.netSide by side
| Figure | iperf3 | M-Lab NDT |
|---|---|---|
| Price from | Free | — |
| Free plan | Yes | — |
| Free trial | — | — |
| Open source | — | — |
| Web | — | Yes |
| macOS | Yes | — |
| Linux | Yes | Yes |
| iOS | — | Yes |
| Android | — | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | — |
| Plans published | 1 | 0 |
| Spec score · Network Testing Software | 8.1 (#10) | 7.7 (#20) |
| Founded | 2010 | 2009 |
| Integrations | iperf3 was developed initially as the bandwidth tester for the perfSONAR measurement suite, which the project identifies as its primary user base. | M-Lab publishes NDT data through BigQuery and archives raw measurement data in Google Cloud Storage. |
| Protocols | It measures TCP, UDP, or SCTP throughput and includes both client and server functionality. | NDT supports ndt5 for compatibility with legacy clients and ndt7, which uses TCP BBR where available and operates on HTTP(S) ports 80 and 443. |
| Purpose | iperf3 measures achievable bandwidth on IP networks and reports throughput, loss, and other test results. | NDT measures a connection’s capacity for bulk transport and reports upload speed, download speed, and latency metrics. |
| Support | The project provides a developer mailing list and GitHub issue tracker for questions and bug reports. | M-Lab directs NDT users to contact [email protected] for support. |
Plans
In their own words
iperf3
iperf3 is a free command-line network measurement tool that reports achievable IP-network bandwidth, throughput, loss, and related results. It includes client and server functions for TCP, UDP, and SCTP tests, with adjustable timing, protocol, and buffer settings. Client or server output can be emitted as JSON, including line-delimited JSON for real-time parsing, and a library version can be embedded in other programs. The project uses a three-clause BSD license and lists Ubuntu Linux, FreeBSD, and macOS as its officially supported platforms. Windows is not officially supported; its FAQ points users with Windows problems toward iperf2. ESnet supplies source distributions rather than binary packages and recommends checking SHA256 checksums. iperf3 began as a perfSONAR bandwidth tester, its primary user base. It is not backwards compatible with the original iperf. Version 3.22 was released September 29, 2026.
M-Lab NDT
M-Lab NDT has no write-up on Specifiction yet; its figures are above.