Hi Roadrunner, Thanks for contacting us! You can create a blank canvas at 6900 x 2300px. This will allow for a DPI of 96, which is a little on the low side, however should be of an acceptable quality for a banner that will be viewed from at least a few feet away. You should check with the company producing the banner that these dimensions are large enough for them. Let us know if you have any further questions!