How To:Convert Micro Sim to a Nano Sim

This is a very simple tutorial to convert a micro sim to a nano sim for use on newer phones without buying a new sim card or transferring your number.

We need the big (Micro) to look like smaller (Nano) one.

Use double sided sticky tape to provide a stable work holding. This would also work with hot glue or fixture wax. Amazon sells bulk of this 3m double sided tape, so I just always have a large roll around.

G Code File to run. The start position is bottom left corner. The angled cut will be faced to your right when looking at your machine. Download this file and prepare it for running. I used bCNC to send this gcode, but any sender will work. (1.9 KB)

Set your start position. To ensure better accuracy switch to a smaller bit. I used a smaller bit meant for PCB creation to line up my X and Y axis’s, then switched the bit with the correct .125" bit for cutting. Set your zero, and you are set to run the gcode file.

Once the machine has cut out the old card, double check the fit. If you were off on your X and Y in too far, the sim will be ruined. In this case it fits and looks good.

One minor issue, The Micro sim card is slightly thicker than the Nano sim. You can either choose to skim the top using the CNC or sand. I chose to sand down the thickness by hand giving me more control over the amount of plastic removed. If you can tell by the slightly darker square in this photo, DO NOT SAND TOO FAR! If you sand too far you will ruin the sim.

The last remaining step is semi-optional. I say semi, because depending on the phone you have it may not be required. If you have a sim holder that is made of entirely plastic this step can be skipped. If you have one like mine (metal), you will want to make sure the pads to not make contact with the sim holder frame. It may be hard to see this next photo, but use A razer blade to score the pad, and cut a sliver away from the plastic. This will allow the card to sit in the sim holder frame without making electrical contact.

That is it, I hope someone finds this helpful. This process just worked great for me and my new phone.


ha ha, quite genius. So far every time I’ve done this a scalpel worked