Do copy acceleration utilities actually lower file transfer speeds? Our tests say yes


We’ve featured several file copy acceleration utilities on this site. Recently, however, we went in and did a head-to-head test to discover which of the many free options was the best at increasing copying speed. The results surprised us greatly: all of the tools we tested actually took longer for the file transfer than Windows Explorer.

This was obviously not the result we expected or wanted, so we re-did the test using a different set of files.

When in the first round we used 367 files that collectively amounted to about 474 megabytes, in the second test we used 3 files that amounted again to about the same (493 megs), speculating that perhaps these kinds of copy utilities did better with large file SIZES rather than a large NUMBER of files.

However, the result in both cases was the same. Several follow up measurements on other PC and operating systems also produced more or less the same results.

1. A little background:

I am a long time user of SuperCopier, which I mentioned in a number of places on this site, and have used many of the better known free copy acceleration utilities such as Teracopy, Copy Handler, and others. This article was conceived in order to answer the question: which of the different copy acceleration utilities performed best. It was meant to be a simple test, as described below.

2. The original test concept.

We thought we would install each one of the freeware copy acceleration utilities one after the other and use these tools to copy a battery of files and folders to and from three hard drives with ample free space. We would time these and compare the results, including the results from Windows Explorer without using any copy tool at all. We ended up doing two tests and a handful of follow up measurements.

3. The free copy acceleration tools that were used:

And the control, of course, was Windows’ Explorer’s own copy process.

4. The First test:

  • Files used: 367 files totaling 474 MB. Text files, JPG’s, MP’3, Videos, and Excel files
  • Windows version: Windows Home 64 bit.
  • First transfer/ Internal HD: partition-to-partition on a 7200 rpm internal hard drive
  • Second transfer / External HD: laptop (7200 rpm)-to-external USB drive (5400 rpm)

We ran test twice, just to verify, on a different laptop, although it has the exact same specs above.

    4.1 Results for the First test

    See the table below.

    First attemptIntenal HDExternal HDSecond attemptIntenal HDExternal HD
    FF Copy‘00:18:982‘05:20:229FF Copy‘00:12:418‘04:57:721

    Windows on its own came out on top, and sometimes by a mile. There were strange variations between the transfer on the internal hard drives vs. the external USB drive. However, it seemed that no matter which copy acceleration tool, transfers simply took LONGER across the board.

    This is not what we wanted or expected, so we decided to try again, as described below.

    5. The Second test:

    • Files used: 3 files totaling 493 MB. All were large Excel files
    • Windows version: Windows Home 64 bit.
    • First transfer/ Internal HD: partition-to-partition on a 7200 rpm internal hard drive
    • Second transfer / External HD: laptop (7200 rpm)-to-external USB drive (5400 rpm)

    5.2 Results for the Second test

    Internal HDExternal HD
    FF Copy‘00:19:278‘04:20:177

    Again, the results were similar to the first test, which showed that the number of files vs. size in megs was not the factor that lead to this result, that it was not an issue.

    6. More measurements.

    We did two follow-up measurements afterwards out of curiosity:

    1. We took the same files as the ‘Second Test’ above, and tested only FF Copy (since it was the best performer) on a 32 bit virtual machine. The results were the same
      • Windows: 00:22:80
      • FF Copy: 00:24:23
    2. We copied a 21.7 GIG folder containing 8 files on Windows 7 64bit, from an internal SSD drive to a 5400 rpm external USB drive.
      • Windows: 17:34:25
      • SuperCopier 2: 17:45:04

    7. The conclusion

    It seems to me that, aside from the advantage of being able to pause and resume file transfers, there is no gain to be had from using any of these copy acceleration tools, and in fact they have the adverse effect of slowing down your transfer.

    The possible exception to this is FF Copy, which at best perormed more or less on-par with Windows in the tests above.

    Your thoughts and insights would be extremely welcome.

    • You probably tested this with win7.
      There is a difference between XP and 7.

      • Marc Klink

        Yes, it is documented in a few places that the large transfer performance of Windows, all the way up to Windows 7, was pretty bad, sometimes stalling out almost completely, due to problems with the Windows cache scheme – the documentation also cited performance values from the guys who wrote Winternals utilities – very knowledgeable guys, and now one is a part of Microsoft itself.

        On XP and Vista Teracopy is much faster on multiple copies of files which total in the hundreds of megabytes. I know that Windows own routines are faster for smaller stuff, but I like the extra features of TeraCopy, and also use it out of habit.

    • suja ram

      Surprising results
      I use super copier and I like the interface

    • Womble

      When these tools started to appear on the scene I tried one and found similar results, albeit with a much more basic test.

      Most of them, if not all, probably just make API calls anyway which probably eliminates any potential for improvement.

      Thanks for the good quality post.

    • kwacky1

      Yeah I’d like to see the tests done on XP as well because that’s when I started using SuperCopier (and still do at work!) and have just become accustomed to having it installed.

      Win8 will probably remove my need for SuperCopier though.

    • It is most likely that the internal code on all of these “accelerators” is performing system calls to the Windows file copy routines in the kernal. I would expect no speed improvement in that case (on Windows 7; XP’s GUI copy is in essence the same as any other GUI copy utility, making calls through the same interface the accelerators do).

      It would be instructive to see if XCOPY in a CMD window performed better or worse than the Windows 7 GUI copier.

    • Adam

      Title is wrong – should be “Do copy acceleration utilities actually worsen file transfer speeds?” Saying it lowers them implies it takes less time, which would be good.

      Thanks for your tests. I use TeraCopy mostly for the reason that it won’t kill the job part way through if it has trouble copying one file. I think I will switch back to the default Windows copier but keep TeraCopy around for the important jobs.

      • Daniel

        I use TeraCopy for the exact same reason, also it seems more clear in listing errors, files that he could not handle, etc. It’s more a reliability reason than speed.

        • taa

          Same here. Looks like I’m going to switch to FF Copy as it also won’t abort at the first sign of trouble when copying a file.

      • Colin

        “Title is wrong – should be “Do copy acceleration utilities actually worsen file transfer speeds?” Saying it lowers them implies it takes less time, which would be good.”

        I agree that the title is poor. However, “…actually worsen” also seems very cumbersome. I think the original question is phrased badly altogether.

        “Do copy acceleration utilities actually speed up file transfers? Our tests say – No.” is less ambiguous IMHO.

        • Samer

          @ Colin: but that also doesn’t communicate the message “hey — those file copy utilities might actually be slowing down your transfers”. Which I think people should know.

      • Doc

        No, the title is correct as it is…lower speeds would mean the process takes longer, which is the point of the article. Higher speeds would mean the copy goes faster.

    • Farow

      On Windows XP, I tried copying three files that add up to 1.77 GB with the Windows copier and with TeraCopy and there was only a difference of two 1298 milliseconds (measured with autoit, Windows: 66737, TeraCopy 68035)

    • I was under the impression that TeraCopy’s free edition limits your file transfer rate. I’ve been using SuperCopier2 for a pretty long time now, and I’ve got to say — for copying over the network (from one MACHINE to another), it beats the pants off of Windows’ internal method. For copying files within the same system, I tend to disable it.

    • I always thought the same and never used any of these software. Plus with the coming of Windows 8, the new in-built windows transfer comes with a pause support, something they should have done long ago. Really nice work on testing and trying out so many software, and this will clear a lot of people thinking about copying applications.

    • Fred Thompson

      RichCopy (look for version gives pause support and more control than WinXP or Win7 copying. I’ve never seen any accelerator actually increase speed. Maybe there was a benefit with Win95 and FAT but, in that case, xcopy was faster than copy.

      • Samer Kurdi

        Fred. Indeed I will have to add Richcopy to the list, if I am ever motivated to redo this 😉

    • I agree with those who say the main value of these utilities is their ability to recover or skip files that would otherwise break an hour-long copy at some random point using the default Windows copy utility.

      The interfaces are also much better, allowing more control and more information displayed as to the state of the copy.

      Sorry, but speed isn’t the only thing that matters in copying – although if you are copying GB of files, then obviously it does.

    • > It seems to me that, aside from the advantage of being able to pause and resume file transfers, there is no gain to be had from using any of these copy acceleration tools

      FastCopy also has a transfer verification tool to make sure the files are copied correctly, and there are some overwrite options that are helpful. But it was clear with even limited testing that FastCopy is not “fast”. I hadn’t tested any of the other tools out there so I’m glad to see your article.

    • anonysubscribe

      very insightful and more relevant than some of the involved reviews.

    • jfjb

      Hello Samer,
      I suppose the Windows and utilities ‘copy’ command was used with the same paramater — i.e. w/o ‘verify’ — which would increase not only time but also reliability.
      Someone mentioned SuperCopy over networked computers, I do agree that the GB connection shows a speedier file transfer, but I haven’t timed any test.
      Thanks again for your investigation, it does make sense that the OS itself should be more performant since it directly uses its own internals. Too bad MS didn’t include a GUI as versatile as the tools you mention. Russian brute force style has some truth to it… no pun intended, but it was fun to talk to you once more over yet an additional piece of information worth the trouble of reading it to the end. Thanks.


    • jasray

      Missing the biggie and best–RichCopy.

      Awesome utility long forgotten.

    • Alan

      I wonder if going to the command prompt and using the old DOS copy command would be faster for bulk copying.

    • Krishna

      A much needed investigative review. Agree with the results.

      Samer, you must also look at external download managers vs browser downloads. Copy/move and downloads are the two most used utilities.

      A few days ago I bought a new external USB storage. Reorganization is always a nightmare. I moved 20 gig with tera copy which was moving at 18.3/18.9 MBps, suspected it was slow, uninstalled and continued with Windows. Surprisingly, Windows moved files at a minimum of 22 MBps and for some files it touched 24 MBps. I stick with Windows now on 7. Though on XP tera copy does a great job.

      A very good post.

    • I use BurstCopy ( it’s a paid program ) . But I mainly use it because I copy a lot of files ( especially small sized image files ) and copying fails sometimes . And I need to know which file failed to copy . So mainly I use it as a copy ” manager ” than a speed accelerator .

    • How about WinMend File Copier? It’s free and claims to be 300% (3x) faster than the O.S.

      Btw… if you copy over a LAN then you really should use a copy setup like RSync or something that understands Reed/Solomon encoding (i.e. ‘repairing’ data so it does not have to be sent over the network).

      • Samer Kurdi

        @ Adrianus: will add it to the list, if I ever redo this 😉

    • rickxs

      Do copy acceleration utilities actually lower file transfer speeds? Our tests say yes

      your tests say no — stupid title

      • Rob

        The title is technically correct grammatically. It sounds wrong because one might intuitively expect the title to be “Do Copy Acceleration Utilities Actually Lower File Transfer TIMES?” in which case the answer would be No. However the title actually refers to file transfer SPEED. If you are driving your car and you lower your speed, that means you go slower. Same principle applies here. Nonetheless, it IS confusing. I would suggest a less ambiguous title such as “Do Copy Acceleration Utilities Actually Decelerate File Transfers?”, or if you want to use simpler words, “Do Copy Acceleration Utilities Actually Slow Down File Transfers?” or “Do Copy Acceleration Utilities Actually Result in Slower File Transfers?” (Although to me decelerate seems no more complex a word than acceleration, and since you use that word, it only seems logical to use the word’s exact opposite as the verb) Sorry…I was a Copy Editor in a previous life. I actually find this kind of thing interesting for some reason… 🙂

    • Boris

      I do not use TerraCopy to get mind-blowing file transfer speed. I just want to make sure that everything that supposed to be copied is copied and it can be verified. Also Windows copy function freezes quite often on transfer of many small files. TerraCopy does not have this problem.

    • seba1976

      Sorry Samer but I don’t believe you. There 3 scenarios to try: 1) copy from one drive to another, 2) copy from one drive to another over the network, and 3) copy between different areas of the same partition. From those, the one you’ve picked is the most difficult to test and compare. You have to take into account things like drive speed over different areas of the disc, fragmentation (specially the one you introduced doing the tests), etc.

      In any case, copying large amount of data over the same drive is wrong. No one should do that. The utilities are not designed to do that.

      Over the network and over different drives, the utilities should at least perform the same as win7.


      • Samer Kurdi

        Which part do you not believe?
        (1) copy from one drive to another — tested, results are above under ‘external’ heading, disappointing across the board
        (2) copy from one drive to another, over network — did not test
        (3) copy between different areas of the same partition — there is no copying involved in moving across different areas of the same partition. It is instant

        You say ‘copying large amounts of data over the same drive is wrong’. I am assuming you mean across different partitions on the same drive? In any case, this would describe 90% of the copying that I do on my laptop, and it seems perfectly reasonable to test (labelled ‘internal hd’ above.

    • Yamamoto

      If you use SuperCopier option “buffered copy” this can really accelerate the transfers. Please try it in your test.

      • Samer Kurdi

        hmmm. Indeed I will have to check this option out.

    • Skrell

      I had to weigh in on this too. I use WinXP SP3 and ran a quick test where i copied 618MB of files from 1 directory to another on the same drive. Outcome: Teracopy copied them in 2:06.2 minutes whereas windows took 2:38.6. Had the test been closer i would have reran it, but this is all the info i need to keep me using teracopy for now!

      • Samer Kurdi

        @ Skrell: yes it seems from your test and what others have said above that the copy process in XP is significantly different than that of Windows 7, which apparently was much improved.

        At the time of the writing of this article we had no access to a Windows XP machine, so we didn’t run the test on that OS.

        Thanks for your input.

    • When copying large amounts of files onto my external to back them up, TeraCopy was much, *much* faster than Windows’ built-in copying utility. I was copying upwards of 70gb, and not only did Windows take longer, it was more likely to hit an error and stop partway through. While your tests indicate otherwise, Teracopy was faster for me — and the lack of freezing halfway through kept me from going crazy as I tried to copy large batches of files to my external hard-drive overnight. Windows’ utility just wasn’t cutting it — I hated waking up to find out that the job wasn’t done, or was only done because it had crashed.

      Teracopy helped me to preserve my sanity. (And my harddrive contents.)

      • Skrell

        what was your OS??

    • Brousse.Ouillisse

      Dear Samer,

      The results shown by your tests are VERY surprising to me. I am a SuperCopier fan for a long time now and do agree that the developper team’s website seems not updated for a long time since version 2.2 so called beta (never had any issue with).
      However, I always found the copy to be as fast as Windows 7 explorer. I mean, not with such a difference in the results !
      TeraCopy is not my choice for an installation (as I think is not so good as SuperCopier) but OK for a portable version.
      As you say as a conclusion, pausing and resuming copy is appart your test, but it matters when it is about incremental copy. In addition, Supercopier can save, restore, sort the filelist and in addition, can limit the copy bandwith, very useful when copying files from one computer to another via network, so the hosting PC hard drive is not fully busy because of the copy process.
      I’ll continue to install SuperCopier on any newly installed Windows system as it is too useful to simplify quick backups. Too many people avoid this maintenance operations because of the time it taks, but with fast incremental copy SuperCopier fasten the process.

      As usual, many thanks for your fab work founding new freeware nuggets 🙂

    • freewareer

      has anyone tried ultracopier? I’ve been using it for some time now (since version 0.20); seems stable enough and it works pretty well… though I haven’t made any speed comparisons.

    • Clemens Ratte-Polle

      on xp copy utilities are better than xp internal routine.
      but speed is not everything.
      on my old machine the copy processes slow down my pc, nearly blocking explorer, so i must wait the copy process… 🙁
      with copy helpers there is a fluent workflow available. copy utils do their work in the background and do not disturb you. it feels like they lower down the copy process priority on purpose not to use the harddrive too much by copying.
      so real multitasking on computers means not to give every process the same time and priority. the foreground process should always be the highest task.
      or are you waiting each copy job for minutes, doing nothing than waiting, looking at the flying files?^^
      copy utilities do their silent jobs 🙂

    • How about testing again on Windows 8?

    • Insomniac

      Thank you for your effort in comparing these copy ‘accelerators’ – I must admit that the results do surprise me, but if I may add my 2 cents worth in commentary to your blog.

      I personally prefer to refer to this genre of applications as copy ‘managers’. As a long time user of SuperCopier2 (v2.2b), I find that I cannot go back to the generic Windows Copy handler – with SuperCopier2 or any other ‘manager’ I can check the copy queue, bump certain files up or down this queue, remove a particular file, preview the copy queue, pause and resume (e.g. while a removable drive is having connection issues) and so much more.

      In my experience, I have noticed that typical copy usage does not always involve a simple select, drag and drop – it does not end there. As a multimedia hoarder, I have noticed that one typically selects a particular file or folder, then drags or copy-pastes, then searches and selects another file or folder and again drags or copy-pastes, and so it goes on…
      Using the innate Windows Copy, after about the 3rd drag & drop I generally notice a severe slow-down as each copy process seem to collide with each other bringing throughput down dramatically. A copy manager on the other hand queues all these files so that they copy one at a time, at the maximum throughput possible, as you continue to add more files to the copy queue.

      I would personally like to see a speed comparison with multiple Windows Copy processes running together, not that I refute your results in any way. I would be very interested in those results…

      Of course I have noticed a speed decrease using a copy manager if I am copying many small files such as JPGs or TXTs, but I still prefer the copy management facilities that a copy manager offers over Windows Copy.

      Thank you for taking the time to test and provide your results – you have opened my eyes to a lot of alternative options.

      PS – I would personally recommend a rename of this blog to “Do copy management utilities actually improve file transfer speeds? Our tests say no”, (note ‘improve’ vs ‘lower’) but perhaps I am just being @n@l about most people’s understanding of your headline…


    • omeletted

      Raymond recently did similar testings, and arrived at a slightly different conclusion. ^_^;; So which do we trust now lol

      • jackuars

        Well Raymond for sure in this case, and FastCopy is really fast even in my tests.

    • Try alternate free portable file copier software exshail copycare form below site.

      You can Preview list of files before copying with seven options below.

      1. “Source > Target – Copy Files New and changed from Source”
      2. “Source > Target – Copy Files New From Source”
      3. “Source > Target – Copy Files Changed from Source”
      4. “Target > Source – Copy Files Changed from Target”
      5. “Target Source Copy Files having Size Difference”
      6. “Delete Files Orphan from Target”
      7. “Source = Target – Copy Exact to Target – Overwrite All (Delete Orphans from Target)”

    • gamick_lisafisher

      “Long Path Tool” is a great utility to copy and delete files.I am really impressed by this tool as it handles long files for copying as well as deleting.