Wondering what your kid should be for Halloween? If you're a parent to one of the 26 percent of American children who haven't decided on a costume yet, look no further for ideas. The No. 1 choice for children dressing up this year is princess, followed by Batman character and superhero, according to a survey by the National Retail Federation. About 2.1 million kids will be animals, and another 2 million will be a character from the 2013 Disney movie "Frozen."

“As we’ve seen for several years, Hollywood and pop culture both have a tremendous impact on how adults and their children decide to dress the part each Halloween, and it’s evident some of the biggest newsmakers of the year will be out in full force this fall,” the federation's president and CEO Matthew Shay said in a news release.

The federation analyzed responses from about 6,800 parents between Sept. 1 and Sept. 8, and many of the trends they found were reflected on other websites. "Star Wars," "Batman" and "Frozen" characters made the top 10 most popular kids costumes on eBay, but its No. 1 was a classic: Mario and Luigi. Walmart found that for girls, Dorothy from "The Wizard of Oz" and the Pink Power Ranger were most desired. For boys, "Ant-Man" and "Teenage Mutant Ninja Turtles" won out.

Here are a few popular -- and easy -- Halloween costumes for kids:

1. Zombie. As the No. 7 most popular getup for kids, according to the federation, this costume can take a variety of forms. Use powder to make your kid's face deathly pale, then apply fake blood made from red food coloring, gelatin and water. Splash the blood on a white shirt, smear with dirt and wear with tattered jeans.

2. Minion. Who can resist these little guys? It's not difficult to create the 6th most popular kids costume on eBay. Just have your child don a yellow hood with denim overalls and black boots. Add silver goggles, black gloves and pipe cleaners on top for hair. Don't forget to speak minion language.

3. Power Ranger. The perennially popular superheroes from the 1990s are back again -- and dominating Walmart sales. To make your own Power Ranger outfit, Carrie Elle recommends using black, silver and gold duct tape on a shirt in your favorite color and pair with black leggings. Make your own cardboard mask per these instructions.

4. Pirate. Pirates are a classic for any Halloween party. Dress your kid in a striped shirt, felt vest and boots. Make a pirate hat by stapling the sides of two black pieces of shaped cardboard with a skull and crossbones logo on it, and hand the child a hook. Add an eyepatch and a plastic sword for good measure.

5. Minnie or Mickey Mouse. This ninth-most-popular eBay costume for kids is easy to make if you glue felt ears to a black headband, put on red shorts with a black shirt and draw a black eyeliner nose on your face. Add yellow shoes, white gloves or whiskers to step it up.