These sites offer plug-ins that can be downloaded on web browsers, such as Chrome or Safari, and some of these tools can do your bargain-hunting homework. These are five of the best browser extensions for online shopping.

Honey

Honey is a browser extension that promises to help you find and automatically apply the best coupon codes at checkout before you complete an online order. So rather than opening a separate tab and searching for coupons and sales from coupon aggregator sites, you just shop as usual and let Honey do the work for you. Available for Chrome, Firefox, Safari and Opera.

Ebates Cash Back Button

Similar to Honey is Ebates, a cash-back website that calls its browser extension the Cash Back Button. Members can use the button to activate cash back directly at store sites —rather than clicking through from the Ebates portal first — and automatically apply coupon codes at checkout. Unlike Honey, cash-back percentages aren't a surprise at Ebates. Compatible with Chrome.

Goodshop Fetch Button

Goodshop helps its members locate deals and donates a portion of purchases by an eligible member to the shopper's school or charity of choice. Install the extension to activate coupons, which will automatically appear on your screen, and a donation. Users will be able to see the available donation percentage in their search engine results page for a given store. Available for Chrome, Firefox and Safari.

Camelizer by CamelCamelCamel

CamelCamelCamel tracks the price history of items sold on Amazon so shoppers can get a sense for any given product's regular price — and thus judge when a sale is really better than the ordinary selling price. The Camelizer extension provides users with price history charts without having to leave a product page on Amazon. Supported by Chrome, Firefox and Safari.

Slice Watch

Slice Watch monitors prices so you don't have to. When users shop at supported retailers, such as Amazon, Target and Best Buy, they will see a teal icon in the top right of their browser. Click it when you find an item you like and want to track. Slice Watch, which can be added to Chrome, will alert you when that product goes on sale or is reduced in price.

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