Add some water to your water bath canner and set your canner on your stove, but don't turn the heat on. Make sure to add your jar rack.
Fill your quart jars with one and one-fourth cups to one and one-half cups of frozen or room-temperature cranberries. Fill the rest of the way with warm water but make sure you leave an inch headspace at the top. If your berries are frozen, allow them to thaw before canning.
When all your berries are thawed and you fill the jars with water leaving an inch of space at the top, wipe the rims of your jars. Clean rims are necessary to make a good seal with the lid.
Put your new, clean lids on your quart jars and tighten the bands to fingertip tight. That means you screw the bands on until you just meet resistance and screw a little bit more.
Put your quart jars in your canner rack, lower them into the water, and adjust the water to make sure the jars are covered with at least two inches of water. If you have hard water and want to prevent mineral build-up, add a little bit of distilled white vinegar to your pot of water.
Put the canner lid on and turn on the heat to start boiling your water.
Once the water is boiling, set your timer for 25 minutes to create a good berry juice inside each quart jar.
After 25 minutes, turn off the heat and remove the canner lid. Wait 5 more minutes and then remove your jars using your jar lifter, cool overnight, and store in your pantry. Make sure to always label your canning jars with the contents and the date and remove the bands or rings from each jar before storing them. *This general berry juice will continue to develop a more concentrated flavor over the next month or two, so try not to open up your jars until it develops its full flavor.