Internet-Speedtest — Kostenloses Online-Tool

Free Internet Speed Test — Download, Upload, Ping & Jitter

Toololis Internet Speed Test measures your internet connection performance directly in your browser. Test your download speed, upload speed, ping latency, and jitter in under 30 seconds. The tool provides a connection quality grade from A+ to F, giving you an instant overview of your internet performance.

This is a browser-based speed test, meaning all measurements happen through standard web requests. While not as precise as dedicated native speed test applications, it provides a quick and convenient way to check your connection without installing any software. Nein sign-up, no ads, no tracking.

What the Test Measures

• Download speed (Mbps) — how fast your connection can receive data from the internet. This affects video streaming, web browsing, file downloads, and cloud services.
• Upload speed (Mbps) — how fast your connection can send data to the internet. Important for video calls, uploading files, live streaming, and cloud backups.
• Ping / Latency (ms) — the time it takes for a request to travel to a server and back. Lower is better. Critical for online gaming, video conferencing, and real-time applications.
• Jitter (ms) — the variation in ping times. High jitter causes inconsistent connection quality, leading to choppy video calls and lag spikes in games.

Understanding Your Results

The connection quality grade summarizes your overall internet performance. Here is what the grades mean in practical terms:

• A+ (Excellent) — 100+ Mbps download, under 10ms ping. Handles 4K streaming, large file transfers, and competitive gaming simultaneously.
• A (Great) — 50-100 Mbps download, under 20ms ping. Comfortable for multiple HD streams, video calls, and fast downloads.
• B (Good) — 25-50 Mbps download, under 30ms ping. Sufficient for HD streaming, video calls, and general use for a household.
• C (Fair) — 10-25 Mbps download, under 50ms ping. Can handle one HD stream and basic browsing. May struggle with multiple users.
• D (Slow) — 5-10 Mbps download, under 100ms ping. Limited to SD streaming. Neinticeable lag in video calls.
• F (Very Slow) — under 5 Mbps download or over 100ms ping. Basic web browsing only. Frequent buffering and lag.

Tips for Accurate Results

• Close other browser tabs and applications that use the internet.
• Pause any active downloads, updates, or streaming services.
• Use a wired (Ethernet) connection instead of Wi-Fi for the most consistent results.
• Run the test multiple times and compare results — internet speed can vary throughout the day.
• Test at different times of day to identify peak congestion periods.

How Browser-Based Speed Tests Work

Browser-based speed tests work by downloading and uploading data through standard HTTP/HTTPS requests and measuring the throughput. The download test fetches files of increasing size from CDN servers and calculates the transfer rate. The upload test sends generated data to a remote endpoint. Ping is measured by timing small requests to fast CDN endpoints.

Browser tests have some inherent limitations compared to native applications: JavaScript execution overhead, browser connection limits, and HTTPS encryption overhead can all slightly reduce measured speeds. Results are typically within 10-20% of native speed tests, which is accurate enough for general diagnosis.

When to Contact Your ISP

If your measured speed is consistently below 50% of what you are paying for, contact your Internet Service Provider. Before calling, run the test multiple times at different times of day, and on a wired connection. Document the results to share with your ISP's support team. Also check if your router firmware is up to date, as outdated firmware can cause speed bottlenecks.