Using "Save for Web" will automatically decrease the resolution of your graphic to 72 DPI. This will result in a smaller image, lower quality, and will not perfectly fit in our editor if you're using our design templates.
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Therefor we always recommend to use "Save As..." within Illustrator and Photoshop to maintain the highest quality of your file.
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Simply click on File → Save As... and save your file in either PNG or JPEG at the highest quality settings.
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