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Do not DM me over this tool anymore. It is no longer being supported and I have no copy of it left.

How to change the MP3 file with audacity
0. If you need to download audacity, click here.
For MP3 exporting, A program called LAME is required. To download LAME, click here

1. After opening audacity, go to File -> Open or press Ctrl-O and choose the appropriate MP3 file. Alternatively, the MP3 file can be dragged into the window.
2. After the MP3 file has loaded, go to Effect -> Change Tempo as shown here:

3: Enter the percent change value you want and press OK. For an example of what value you need to enter, check this chart (The values on the right are the values you enter into audacity):

4. Go to file -> Export Audio or press Ctrl+Shift+E and choose where to save the MP3 file and press Save. The file needs to be saved into the folder of the mapset you are planning to change the rate of. If saved in any other folder, the process will not work. Give your file an appropriate name as you'll need to enter this value later in the actual rate change program.


And now onto the actual program (hopefully this is a stable release).
This program takes in any osu-mania file (and only osu-mania files) and allows a change to the speed of the map to any non-zero value. Simple as that.
This program is still in beta stage and has no error-checking currently so don't try and break it because you will and that's your own fault.
Download link is here. Just extract and run the .exe file.
To see a map where difficulties where created using this program, click here.

A guide to using the program
1. After program has opened, click the Input button, and choose the .osu file of the map that you want to change the rate of and click Open.
2. Enter the name of the mp3 file that you created earlier into the box labelled "Audio Filename:"
3. Enter the speed % into the last remaining box as labelled on the program and press "Go". Once the file says "Conversion Complete", then the file is created.
4. Go into game and enter the song select menu unless you're already in the song select menu, and then press F5. The file should now show up working fine.

  1. Alpha 1.0: Program running but only supporting the majority of v14 files.
  2. Alpha 1.1: Added support for v12 files.
  3. Alpha, the v12 patch update: Enabled support for v12 files.
  4. Alpha, the colourful patch update: Added support for a file that contains combo colours (broke previously, found thanks to Zenx).
  5. Alpha, the musical patch update: Added support for internal hitsounds, events and bookmarks.
  6. Alpha, the musical mini patch update: Removed files that are unnecessary to the public, reducing the file size by 85%.
  7. Beta, the accessibility patch update: Added support for decreasing rate values (values below 100%) as well as posting to the forums for more people to access, as well as a hotfix to missing notes.

Since this is in beta, and the files in alpha have had minimal testing, bugs are expected and will show up. If any bugs that are not expected (aka if you enter 0 in the rate change and tell me there's a bug you're going to get slapped), please post as a reply in the forums and I should have hotfixes out within 24 hours.
Files that have multiple bookmarks and have a Storyboard layer 0/1/2 are most likely to break at the moment. If this does happen, report immediately.

On top of that, if there are any features you would like to see except for the ones mentioned below, feel free to leave a reply and I'll see what I can do to implement them.

Current planned features:
  1. automatic MP3 file rate changing
  2. external storyboard support (maybe cancelled)
  3. video rate changing (that goal is somewhere far off in the future)
  4. continued support for any previous and future changes to the osu file system.

Have fun with those new files!
ayyy lmao ƪ(Ơ̴̴̴̴̴̴͡.̮Ơ̴̴͡)ʃ dis be sum gud shit
Why haven't I found this before... :?
very nice program.
pleas fix link error :(
I got this message :

Processing beatmap headers failed. This map is likely corrupt.
And I did what your guides said..
yeah it looks like bpm is not regular
ok so it doesn't seem to work for me. I used Audacity to change the speed of the MP3 and then saved it to the copy version of the beatmap folder i wanted to change. Then I used the program and made sure I put the title exactly the same as what I named the MP3 File. Which both the beatmap and the Mp3 appear in the beatmap folder with the same file name (just different extension) yet I still hear no audio when I play the map

Edgar_Figaro wrote:

yet I still hear no audio when I play the map
go into the new .osu file and make sure the song used for the map matches what you intend it to be
EDIT 3 (the last one i hope):
after having worked with this program for a while i have found a few things that need to be fixed
First of all:
Processing beatmap headers failed. This map is likely corrupt.
this is caused my some errors of the converter, here are the details
this is how it is and

and this is how it should be

can you see it? the commas between the long numbers are actually supposed to be commas and have to be replaced.

another thing that i have mentioned in a previous edit is that the decimal dots (.) get lost when transferring SVs with decimals

(map is planet//shaper)
you can see the unedited converted version to 0,8x and on the right you can see the regular 1,0x version
as you can see, the offsets are correct but the decimals from the SVs are missing, which is irreparable in a SV map
and you cant get around replacing them my using ALT+selection in notepad++

again, im sorry for the inconvenience ive caused.

EDIT: I'm almost right. It's simply large numbers that osu! doesnt like. Shorten them and recheck your BPM AND TIME SIGNATURE.
Sorry for any inconvenience

EDIT 2: I HAVE REALIZED MY MISTAKE (and Hydrias aswell)
when converting the SVs, the decimal dots (.) get lost, so theres nothing you can do about it and replace the SVs from the changed version with the SVs from the normal ver. Use Notepad++ and make use of the ALT+Selectoin function!
before the edit
I'll explain what causes this error

Take a look at your .osu you just made with the converter.
At Timing Points you should find a looooooooooooong number that has many decimals. osu! doesnt like this number.

What I did was round the number to the 4th decimal and there we go: the problem is fixed.

I'd also recommend rechecking the BPM and offset after every conversion.

Take a calculator and multiply the original BPM by the rate youre using (1.1, 1.2, 0.8 etc.).

Then check the time of the first object in your map and set the offset to that.

I'm starting a Google Drive where I'm sharing maps converted to rates, you can find it on my profile.

Good luck!
the puush is broken can you fix it please? Love your maps
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