Slow download speed
In general, bad download speed is not any kind of error of JDownloader but either a user error or caused by other factors which JDownloader has no influence on.
This guide will try to help you to find out why your download speed is bad and how to possibly improve it.
Simply doing any kind of speed-test will most likely not help you to resolve download speed issues!
In all cases, you should always compare the speed in JDownloader vs. the speed in your browser by downloading the SAME file over the SAME connection with the SAME account(s) in the SAME period of time.
If you are using a proxy/VPN in JDownloader, make sure you're using that in your browser too if you want to get meaningful test results.
In a lot of cases you will notice that the speed you get via browser is the same you get via JD which would indicate server issues/slowdowns of the service you are trying to download from.
A common misconception: The speed unit | Mbit/s vs Mbyte/s | You might get full speed and don't know it.
You might think you're not getting the max possible speed while you are already at max speed.
While your ISP may advertise your connection as for example Gigabit Internet with 1000Mbit/s grants you a max total download speed of 125MB/s.
To calculate between those units, you can e.g. use this link or just use your favourite search engine and let it to the conversion for you e.g. via search term "1Gbit/s to MB/s".
Read more about this topic on Wikipedia.
Slow download speed when downloading from video/streaming websites?
Some streaming sites have bandwidth limits in place - especially those that do not provide any comfortable ways to download their content e.g. a download button on their website.
They're basically limiting the max. download speed somewhere near the max. bandwidth of the currently streamed video quality.
They do this to ensure that users who stream the video can do so without any lag and and the same time prevent bandwidth bottlenecks caused by users who are downloading instead of streaming.
In such a case there is nothing you can do about it.
Slow download speed because of JDownloader connection settings?
Check your connection settings!
High CPU usage during download?
Check for potential SSL related issues!
Are other users having similar issues with downloading from a specific website?
Check the JDownloader forums and search the web.
If other users have reported similar issues recently, the issue is most likely not on your side but on the hosters' side. In that case you can't do anything about it.
Slow download-target #1?
Sometimes users want to download on remote storage such as a NAS.
Sometimes those are slow for some reasons so to exclude this, test when downloading onto a drive which is installed in the computer JDownloader is running on.
Slow download target #2 | HDD vs. SSD?
Especially for faster internet connections, older HDDs can be the bottleneck when it comes to downloading.
If you have an SSD on the system JDownloader is running on, be sure to let JDownloader download onto that SSD and not on other/older connected magnetic harddrives.
Other common mistakes and problems
- Did you enable a speed-limit by mistake in JD? (Speedgraph does show a red line for enabled speed-limit)
Picture of speedgraph in the top right corner with the red "limit" line, visible while downloads are running:
- Make sure that the pause button is disabled: It is right next to the "start downloads" ("play button symbol") button
- Make sure that you did not enable a speed limit by mistake: See Speed limit and Pause mode settings
- Did you forget to add your premium account?
If you own a premium account for a certain service, you should add it under Settings --> Account Manager --> Add
- Did you disable your premium account by mistake or is there an error-state on it?
If you've added a premium account for a service, make sure it is activated under Settings --> Account Manager
Also check for temporary errors (= account gets displayed in color yellow) or permanent errors like invalid password which would display the account with a red background.
- Did you globally disable premium by mistake?
In the main toolbar there is a symbol with a yellow lock.
This globally enables/disables all premium accounts - make sure it is enabled!
Screenshot:
- Are you a premium user but JDownloader fell back to free account download for some reason?
First answer these questions:
Did you get a captcha, a pre-download wait time or are you only able to start one download at the same time?
If you can answer some- or all of them with yes, add an account usage rule for the website you're trying to download from and try again.
- Does your firewall/AV scanner (for example Avast, MS Defender, Northon) block JDownloader?
Make sure that your firewall does not block JDownloader in any way.
You can check this e.g. by completely disabling it - deactivating it might not always turn it off completely.
If you are using the firewall of your OS only (e.g. "Microsoft Defender") however, it is enough to temporarily disable it for testing.
- Do you use a VPN/proxy for downloading?
VPNs can become a bottleneck when downloading.
Turn it off and try again! In some cases though, a VPN/proxy can actually be the solution (see point 8 "routing issues").
- Apple Private Relay causing slow speed?
If you are an Apple user, turn off Apple Private Relay and try again.
- Does your ISP have issues?
There are various speed test websites out there - grab one and test the max. speed you're currently getting via your ISP.
Your issues might as well be caused by routing issues so better test with multiple different speed test websites.
Also possibly test the same download at a friends house, preferably a friend who is using another ISP than you are using.
In the case of routing issues, using a VPN can improve your download speed so give it a try.
- Does the service you want to download from have server/speed issues?
Search the web to find out if there are currently any reported issues with the service you're trying to download from.
In this case you would definitly have to contact the websites' support - the JDownloader support will be unable to help solving issues which 3rd party services are having!
- Is your issue connected to the device you're currently using?
Test the same file via the same account with the same connection (proxy/VPN/external IP) on other devices in your network to find out if your issue is e.g. related to the device you are currently using.
If you're on a shared network (university network/company network), maybe the overall load is high.
If your device is connected via WIFI, connect it via LAN cable and see if you get better speeds then.
- Does the issue only happen with a specific file?
Check if you can reproduce your issue no matter which file you are downloading (download files from the same website).
In some cases, some files might be stored on overloaded servers so out of many files you may try to download, only single files have a slower download speed.
In this case all you can do is wait or accept the low download speed.
- Wrong IP Version in use or bad speed because of overloaded IPv4 routes?
JDownloader should automatically detect IPv6 connectivity and you for it on your own via e.g. ipv6-test.com.
If this detection of JD fails for some reason, this may cause slow download speed.
Try the following:
Go to Settings -> Advanced Settings -> Search for InternetConnectionSettings.preferredipversion -> Set this to IPV6_IPV4 (or IPV4_IPV6) -> Restart JDownloader and check if speeds are better.
Important: Reset this setting to default (SYSTEM) if you do not notice any changes in downloadspeed.
Only contact our support regarding download-speed issues, if:
- Speed in browser- and JDownloader are clearly different
- You've gone through this troubleshooting guide and were unable to identify any other causes of your speed issues other than presumably JDownloader
