I have a Bitcoin installation on an SD card, and the blockchain files (blk0001.dat specifically) take up nearly 4 GB of disk space.

Can the blk0001.dat and blk0002.dat files be safely deleted to free up space on my SD card? Will the blockchain just be downloaded again next time I run my bitcoin client?

  • 2
    You can use a symlink to put the wallet.dat on your SD card while the rest of the data files are including the blockchain are on your hard drive, if you wish. Commented Aug 31, 2012 at 8:23
  • Good idea @StephenGornick!
    – Josh
    Commented Aug 31, 2012 at 11:49
  • 4
    It's a bad idea to symlink wallet.dat! If your client ever shuts down non-cleanly, you may end up with a corrupt wallet. Commented Nov 19, 2012 at 7:41

1 Answer 1


You can delete them just fine, as long as you delete blkindex.dat too. They will be downloaded and processed again. This will take a while, these days, though.

  • Thanks! A while meaning hours... or weeks? :-)
    – Josh
    Commented Aug 30, 2012 at 17:30
  • 1
    @Josh: YMMV but may be about a day. For this purpose you should consider trying a lightweight client. Commented Aug 30, 2012 at 20:38
  • From my personal experience Days (About 1 hour for each week you are behind). This is for my 2.4 Ghz machine. Infinite patience.
    – user20986
    Commented Nov 8, 2014 at 8:30

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.