ndsi-savedumper VS Checkpoint

First, follow dsi.cfw.guide to get homebrew setup on your DSi (you must install Unlaunch or it won't work). Then download DSi save manager and use that to dump your save file. Then you can move it to your PC via the SD Card

For DS (Requires flash cart)For DSi (requires Modding)For 3DS (Requires Modding)

Restore that edited save file to your game using savedumper.

Just to add to this, there's also ndsi-savedumper. It's no longer in active development, but you can get it here: https://github.com/edo9300/ndsi-savedumper

You can use a savedumper (https://github.com/edo9300/ndsi-savedumper) for dumping and injecting saves from and to legit cartridges. If you're playing a gba game on the DSi, you will have to install GBARunner2 (https://github.com/Gericom/GBARunner2) in order to run gba .rom files. I'd try placing your .sav file next to your .rom file and naming them like this: "{filename}.rom" and "{filename}.sav", where the {filename} part is identical.

ndsi-savedumper

If you have a 3DS with custom firmware, it's easy. Just used Checkpoint, it's designed for exactly this: https://github.com/BernardoGiordano/Checkpoint

Save manager app, if you used 3DS.hacks.guide to homebrew it should be already installed (flag icon). Otherwise find it here

I can't remember if this specific method also copies your save game for you, so if the save game doesn't appear on the digital copy, you can use Checkpoint or JKSM to copy your save game from the cartridge to the installed version. You won't lost your save data.

For DS/3DS, you can use Checkpoint on a 3DS to backup saves from carts.

3DS with CFW, using the Checkpoint homebrew. You want the .cia version. DS cartridges sometimes take up to 20 seconds to appear, but always show up at the top left of the icon grid. Backup and restore behave exactly how they do for 3DS games. This is the best and easiest way, do it if you can.

On a 3DS with official carts you can use [Checkpoint](https://github.com/BernardoGiordano/Checkpoint) to back up *and restore* your DS & 3DS saves.

If you have a hackable switch that will get you going in the right direction. Then you need to use Checkpoint to dump the saves.

A quick web search proves this wrong. If you own the hardware and have physical access to the data, you can always make your own backups of it. (And you should, if the data is important. Never, ever, ever trust a cloud provider to backup your data properly.)

To get checkpoint, go here and download the cia file. Put it somewhere on your sd card (it doesn’t matter where as long as you remember where it is) and then open FBI on your console. Click SD and from there find where you put the file. When you get to it press A and select “install an delete cia.” This will install it your home menu and then delete the cia so it doesn’t clutter your sd card (once it’s installed the cia isn’t needed).