Hundreds of retailers are offering free shipping today

If you plan to buy your Christmas gifts online, today is the day to do it.

Dec. 15 is “Free Shipping Day,” a small window of time when several large retailers offer free shipping on all orders and guaranteed delivery by Christmas Eve. All offers are good through 11:59 p.m. ET.

Hundreds of retailers are participating in the event — including Target, JC Penney, Toys ‘R Us, Macy’s, Gap and Old Navy.

In some cases, the retailer will automatically give you free shipping at checkout. In other cases, a special code is required. To help you navigate the options, has compiled a full list with hundreds of participating stores, providing discount information and coupon codes when necessary, as well as additional promotions. For example, Gap is offering up to 50% off everything and an extra 20% off your entire purchase, and Kate Spade is offering an extra 30% off sale items.

In honor of the 10th anniversary of Free Shipping Day, the site has also provided a special category of merchants offering an additional 10% off your order.

Another way to ensure that you’re getting free shipping and other discounts is to download an extension on your internet browser. Extensions like Honey and CouponCabin Sidekick take just seconds to install, and will provide pop-up notifications when discounts and promo codes are available. Honey is available for Chrome. CouponCabin Sidekick is available on Chrome, Internet Explorer, Safari and Firefox.

Brittany is a reporter at Yahoo Finance.

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