I am not exaggerating when I say that discovering pre-cut parchment paper was a life-changer for me. Cooking has become so much less of a chore because clean-up has become so much less of a chore. I no longer scrape baked-on or roasted-on vegetable or meat bits from pans! From roasted brussels sprouts to cookies to homemade oven fries and baked chicken shnitzel, parchment paper makes everything turn out more crisp and lower fat (due to requiring less oil.) They fit perfectly on the standard restaurant baking sheets I use but you can easily fold for smaller sheets or to line bread pans etc

I use parchment for food prep surface, steaming, microwaving, freezing, baking, etc. These parchment sheets work fine, and can stand up to repeated use through a double batch of cookies. They're not my favorite though.

A couple of things to note:
1) These sheets are white, not the parchment colors you see in your Pantone guide. I'm pointing this out in case it makes a difference in the presentation of your baked goods.
2) These sheets are folded in the box. The creases are very noticeable, and you might not be happy about that when folding tulip shaped liner/cups.

The price per sheet is a little higher but not unreasonable. By all means buy and use them if you just need a few for making cookies during the holidays. If you anticipate using parchment regularly, shop for a flat pack of precut half sheets instead.

What about parchment on a roll, you ask? They're okay and you can get them for a good price at warehouse stores, but the tearing and the unrolling... I try not to pick a fight with myself just to save a couple of dollars. Some grocery store chains carry parchment sheets in a pop-up box, which may be the "happy medium" for occasional bakers. Just double check the size.

I didn't measure my cookie sheets before purchasing this item but it is plenty big enough and covers most of the cookie sheet. This is such a great alternative to tearing off a sheet from a roll of parchment paper which often resulted in uneven pieces and rips.
I have used Reynolds parchment paper for years ... including when I was decorating lots of cakes. I would make cones out of it dropping my tips into it rather than messing with washing the plastic cones all of the time.
You cannot go wrong with this product. I was thrilled to purchase these as an "add-on item".

I didn't realize when I ordered this that it's folded into quarters. Annoying. Not nearly as annoying as rolled parchment, but still a disappointment for someone who's been using fully flat parchment sheets for at least a decade.

That aside, it's worlds better than the last pack of parchment I bought: Worthy Liners Half Sheets Parchment Paper Pan Liner - 12" X 16", (250 Sheets) *Free shipping when buying 3 or more any Worthyliners Product*

The Reynolds paper is notably more expensive, but it's thicker and much more grease resistant. I baked two pans of cookies, one with each type of paper:

I love these cookie baking sheets! These sheets make baking cookies so much easier and the clean up is as easy as throwing the sheets when you're finished. The sheets are pre-cut to perfectly fit a cookie sheet the size of a 12x16. They can easily be trimmed or folded to fit a smaller cookie sheet. The sheets are parchment paper which is a must have for me when I bake. The sheets for me take the hassle of using parchment paper that comes on a roll. The sheets take the annoyance of trying to flatten out the parchment paper that curls up because its been in a roll for so long. I also like the fact that these sheets are safe up to 420 degrees and are nonstick. I've never had a problem with the cookies sticking to the baking sheets nor the cookies being unevenly baked.