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Getting Started
Follow these steps to start testing your network with iPerf3 Client & Server:
Add a Server
Go to the Servers tab and add an iperf3 server. You can enter manually or browse public servers from the directory.
Grant Local Network Access
If testing local servers, allow local network access when prompted. This is required for discovering and connecting to servers on your network.
Choose Test Mode
Select Simple Mode for quick tests with preset durations, or Advanced Mode for full control over protocol, streams, and parameters.
Run Your Test
Select a server and tap the test button. Watch the real-time speedometer and charts as your test progresses.
Review Results
Check the History tab for detailed results including speed metrics, latency, jitter, and packet loss. Export to CSV or JSON for further analysis.
System Requirements
- iOS 15.0 or later (iPhone & iPad)
- macOS 11.0 or later (Mac Catalyst)
- Works on Apple Silicon and Intel Macs
- Network connection (WiFi or cellular)
- Local network permission for LAN testing
Frequently Asked Questions
How do I add a public iperf3 server?
Go to Servers > tap "+" > select "Browse Public Servers". Filter by region and tap to add any server from the directory. Popular options include servers from ESnet, Ookla, and various ISPs.
What's the difference between Download, Upload, and Bidirectional?
Download measures speed from server to your device. Upload measures speed from your device to server. Bidirectional tests both simultaneously. In standard mode, "Download" is actually a reverse test where the server sends data.
Why am I getting connection errors?
Common causes: (1) Server is offline or unreachable, (2) Firewall blocking port 5201, (3) Wrong hostname or port, (4) Local network permission not granted. Try a different server or check your network settings.
How do I run the app as an iperf3 server?
On the Home screen, switch to "Server" mode. Tap Start Server to begin listening for connections. The app displays your device's IP address that clients can use to connect. Configure the port in Settings if needed (default: 5201).
What metrics are available for TCP tests?
TCP tests show: Average/Max/Min throughput, RTT (Round Trip Time), retransmissions, MSS (Maximum Segment Size), PMTU (Path MTU), and congestion window size. All metrics are broken down by interval.
What metrics are available for UDP tests?
UDP tests show: Jitter (variation in packet arrival time), total packets sent/received, lost packets, out-of-order packets, and packet loss percentage. These metrics are crucial for real-time applications.
Can I use Siri Shortcuts to automate tests?
Yes! The app provides Shortcuts actions for: Run iPerf Test, Get Last Result, Test Server, and List Servers. You can also use x-callback-url: iperf3cs://x-callback-url/run-test
How do I export my test history?
Go to Settings > Data Management > Export Results. Choose CSV for spreadsheet analysis or JSON for programmatic use. You can also share individual results from the History tab by swiping left and tapping Share.
Why use multiple parallel streams?
Multiple streams can achieve higher throughput by bypassing TCP window scaling limits and better utilizing available bandwidth. Useful for high-speed connections (1Gbps+). Try 4-8 streams for best results on fast networks.
Does the app work on cellular networks?
Yes, the app works over both WiFi and cellular connections. However, cellular networks may have variable performance due to signal strength and network congestion. For accurate results, ensure a stable connection.
How do I report a bug or request a feature?
Email us at chamav@gmail.com with details. Include your iOS/macOS version, device model, steps to reproduce, and any relevant screenshots. You can also use the in-app feedback form in Settings.
Using with iOS Shortcuts
iPerf3 Client & Server integrates deeply with iOS Shortcuts for automation:
Run iPerf Test
Configure server, protocol (TCP/UDP), direction, duration, and number of streams. Returns test result with all metrics.
Get Last Result
Retrieves the most recent test from history. Useful for displaying results in widgets or notifications.
Test Server
Check if a specific server is reachable. Returns boolean success/failure with latency information.
List Servers
Returns array of configured servers. Use with "Choose from Menu" for dynamic server selection in shortcuts.
Still Need Help?
If you couldn't find the answer you were looking for, please don't hesitate to contact us directly.
Thank you for using iPerf3 Client & Server!
We're actively improving the app based on user feedback. Your input helps us make network testing better for everyone.