This is a useful free credit-card sized calendar created by Adam Sporka that you can print out for your own use. The calendar fits on two sides and is not the common one we usually see that crams up all twelve months on the card. All you need to do is to use your thumbs to cover up the corresponding sides and you’ll get to see the appropriate month for an easy date to day check.

Instructions:

1. Find the month you want to read.
2. Use your thumbs to cover the numbers that are not directly below the month header.
3. Note the color of the month header. The last day of the month is rendered in the same color.

Download the calendar (pdf format) here.