121–130 of 216 posts
It's very cool, but I thing the initial download-speed test is very misleading. Consistently I get like 2/3 of my max, but then when I let it run to completion and it goes through the longer download tests it ramps up to my full speed and I get the full value.
Earlier quoted context omitted.
There are decent alternatives for this. Fast.com is hosted by Netflix, making them an excellent speedtest to check for service throttling. Google has a speedtest as well (Google "speed test" and it'll show a button). The more of these tests start appearing, the better.
I've found Fast.com gamed sometimes when traveling in Asia/Europe, in the sense the ISP prioritizes Netflix traffic but normal traffic never gets within 20% of that Fast.com download speed or has much higher latency or something...? With Cloudflare I'm guessing it's a more balanced measure.
The other side of this is why Netflix created Fast.com in the first place: ISPs throttling Netflix traffic (or just having poor peering arrangements that affected it) and blaming Netflix when customers complained about poor video quality (due to Netflix downgrading when experiencing congestion) because some speedtest (that likely the ISP prioritized, or at least knew it had better peering to) gave good numbers.
> With Cloudflare I'm guessing it's a more balanced measure.
Both serve the same purpose for their respective owners: to get good scores on fast.com an ISP can't throttle (or allowed to be throttled by avoidable congestion) Netflix traffic, to get good scores on speed.cloudflare.com they can't throttle (or allowed to be throttled by avoidable congestion) traffic to/from Cloudflair's topologically local DCs.
From a user's point of view using both, plus other tests, gives most meaningful results overall.
305 Mbps for me. Cringy how slow internet connetivity is in the UK.
That's about the same speed for me (in US), and I could get gigabit, but I feel that the ~double cost isn't worth it.
Earlier quoted context omitted.
There are decent alternatives for this. Fast.com is hosted by Netflix, making them an excellent speedtest to check for service throttling. Google has a speedtest as well (Google "speed test" and it'll show a button). The more of these tests start appearing, the better.
I find fast.com massively overestimates my speeds. Interestingly, if you hide the tab running their speedtest you get even higher speeds.
I find fast.com more accurate than most, going by the throughput I see to/from other resources, particularly for upstream rates (which some, including Cloudflair, seem to significantly under-measure). Of course this may vary depending on line type (FTTC, “up to 67Mbit down n& 17 up”, generally seeing more like 50/12) and location (due to differences in local network conditions and peering between you & the speedtest) to I'm not surprised to hear you see the results quite different to those I experience.
> if you hide the tab running their speedtest you get even higher speeds
I suspect this is due to your browser throttling CPU use and timer granularity for background or occluded tabs⁰ reducing the accuracy of the readings, if the code isn't working to mitigate the effect of these throttles on the calculations.
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[0] refs: https://blog.chromium.org/2020/11/tab-throttling-and-more-pe..., https://www.reddit.com/r/incremental_games/comments/jefviz/f..., and many more
Why do these speed tests start out slow and then get faster over the course of a few seconds? Is it something about the internet that means the speed changes so much over the course of the test?
I can't answer your question directly, because I don't know. But the first keyword I would look at would be BGP. Generally speaking, routing decisions are dynamic and constantly changing. Add the unreliability of the network layer, corporate politics and optimization heuristics to that and you get varying results. https://www.cloudflare.com/learning/security/glossary/what-i... https://en.wikipedia.org/wiki/Border_Gat…
Earlier quoted context omitted.
I've found Fast.com gamed sometimes when traveling in Asia/Europe, in the sense the ISP prioritizes Netflix traffic but normal traffic never gets within 20% of that Fast.com download speed or has much higher latency or something...? With Cloudflare I'm guessing it's a more balanced measure.
Fast.com frequently tells me speeds that cannot exist. Why yes, I am definitely getting 1.2gbps over this gigabit Ethernet and 940mbps Internet connection.
It's hard to guesstimate the exact bandwidth of the data that arrives in your browser because of differences in protocol, MTU, header compression and all that nonsense, especially over technologies like WiFi. In my experience, the WiFi throughput numbers seem spot on.
Their compensation makes for some hilarious statistics, but when you're downloading more than 200mbps the fast.com speedtest doesn't make much sense anyway. No way in hell is Netflix going to allow your single home internet connection to somehow pull in a full gigabit of streaming video. If you're your own ISP you can make it happen, but on the other hand you'll probably also know how to get statistics directly from your network hardware, in which case the fast.com numbers are useless but it still becomes a useful way to spike the load.
Netflix's speedtest is mostly reliable for what it's meant to do, which is solve the question of "my internet is fast but Netflix keeps buffering".
Edit: another factor to consider is that accurate timing has been disabled in most browsers because of side channel attacks like SPECTRE. It's possible that those are affecting your measurements at very high speeds.
This one tests a 10MB chunk at last and that's the only reliable indication for me.
100KB and 1MB down/up load tests show unrealistically low values, perhaps due to a high latency (ping).
Is there a cli tool for this aswell or just the website? At home I have my server run a speedtest (ookla for now) running every 30 minutes because I do not trust my ISP to keep their end of the deal. I visualize the results with grafana and would love to change over to this. As haivri points out, this is a very detailed report! EDIT: Apparently there is a nodejs module available https://github.com/cloudflare/speedtes…
I also wonder how much bandwidth I am using by running all of these tests, but my ISP doesn't have any caps so I guess it doesn't matter.
That said, please remember this is a test of you through your ISP to a (hopefully) nearby Cloudflare node. It isn't necessarily testing 'the Internet', since Cloudflare sometimes has creative peering relationships to origins that are not being measured here.
Also, for the people complaining they only have 300 Mb/s -- unless you are streaming multiple 4K movies there is nothing faster about having more bandwidth. You should care about latency, packet loss, and cache hit rate.
Earlier quoted context omitted.
There are decent alternatives for this. Fast.com is hosted by Netflix, making them an excellent speedtest to check for service throttling. Google has a speedtest as well (Google "speed test" and it'll show a button). The more of these tests start appearing, the better.
I find fast.com massively overestimates my speeds. Interestingly, if you hide the tab running their speedtest you get even higher speeds.