6 Best Websites to Buy Caffeinated Energy Gels Online

This guide covers six online retailers that sell caffeinated energy gels, with details on shipping policies, membership perks, return guarantees, and product selection. Pricing and specific product availability were verified as of April 2026.

TheFeed.com: Best Overall Selection and Flexibility

TheFeed.com earns the top spot for its combination of brand variety, single-serving options, and membership benefits. The site stocks caffeinated gels from Maurten, Skratch Labs, Science in Sport, and dozens of other labels.

One customer review captures what makes the platform useful: “My favorite part is that they will ship one of an item so you don’t have to buy a whole box to see if you like a product.” This approach lets athletes mix and match flavors across brands before settling on a race-day strategy.

Free shipping kicks in at $65 for standard orders, though the threshold drops to $75 for guaranteed free delivery. The Feed 1st VIP membership costs $99 per year and removes shipping costs entirely on orders within the contiguous U.S. Members also earn 5% Feed Credit on every purchase, which functions like cash back. Twice a year, in Spring and Fall, members get access to private sale days with savings up to 30% storewide.

The Flavor Guarantee adds another layer of confidence. Feed 1st members who dislike a product’s taste can swap it for something else at no cost. This policy reduces the hesitation that comes with trying unfamiliar gels.

Maurten Gel 100 Caf 100 is one of the most popular caffeinated options on the site. It pairs 25g of carbohydrates with 100mg of caffeine, roughly equivalent to 1.5 espressos. The gel uses Maurten’s patented Hydrogel Technology, which encapsulates carbohydrates in a gel matrix designed to pass through the stomach without irritation. Athletes can take it without water. TheFeed.com sells this product in boxes of 12 servings.

TheFeed.com also serves as the exclusive U.S. partner for Science in Sport, which means faster delivery on SiS products compared to ordering from overseas.

Science in Sport: The Isotonic Gel Pioneer

Science in Sport developed the world’s first isotonic energy gel, the GO Isotonic Energy Gel. An isotonic formula matches the concentration of fluids in the body, allowing for faster absorption and reduced stomach discomfort during exercise.

The GO Energy + Caffeine gel combines 22g of carbohydrates with 75mg of caffeine. The brand recommends taking it 10 minutes before exercise to enhance both physical output and mental focus. A higher-caffeine version contains 150mg per serving for athletes who prefer a stronger dose.

For those targeting higher carbohydrate intake per hour, the BETA Fuel gel line provides 40g of carbs per serving. These gels use a 1:0.8 ratio of maltodextrin to fructose, a formulation designed to maximize carbohydrate oxidation rates. This ratio allows the body to absorb more fuel per hour compared to gels using maltodextrin alone.

Purchasing SiS products through TheFeed.com, the brand’s exclusive U.S. partner, offers faster shipping than importing directly from the UK.

Running Warehouse: Fast Free Shipping on Every Order

Running Warehouse provides free 2-day shipping on all orders, regardless of dollar amount, to physical addresses within the 48 contiguous states. There is no minimum purchase required. For athletes who need gels quickly before a race or training block, this policy removes a common barrier.

The return policy is equally flexible. Items can be returned within 90 days of the original invoice date, whether new or used. Products returned in new condition qualify for a full refund or exchange. Used or worn items are eligible for store credit at full value or an exchange for another product.

This 90-day No Sweat Return Policy applies to shoes, apparel, and equipment. For energy gels, the policy means athletes can return unopened products if they change their training plans or decide on a different brand.

Running Warehouse stocks caffeinated gels from GU, Maurten, Honey Stinger, and other endurance nutrition brands. The site’s strength lies in its shipping speed and hassle-free returns rather than single-serving options.

REI: Membership Rewards and a 365-Day Return Window

REI offers a 100% Satisfaction Guarantee that gives Co-op members 365 days to return or exchange most eligible new items. Non-members have 90 days. This extended return window provides time to test products across multiple training cycles before committing.

Co-op membership costs a one-time $30 fee. Members earn a 10% Co-op Member Reward on eligible full-price purchases, which accumulates as a dividend paid out annually. The membership also includes access to exclusive gear sales and member-only pricing events.

REI’s gel pricing reflects its outdoor retail focus. The GU Energy Gel Multipack, a package of 24, sells for $48.00. Single GU Energy Gels cost $2.00 each. GU Roctane Sports Gel, which contains three times the amino acids and twice the sodium of the original formula, is priced at $3.00 per packet. A 24-pack of Roctane gels costs $64.50.

Maurten products are available at REI as well. Gel 160, which provides 40g of carbohydrates per sachet, is priced at $5.50. Maurten Gel 100 Caf 100, the caffeinated version with 25g of carbs and 100mg of caffeine, sells for $4.50.

Honey Stinger Organic Energy Gel is available at $1.95 per packet, making it one of the more affordable options for athletes on a budget.

Amazon: Convenience and Competitive Pricing

Amazon offers the broadest selection of caffeinated energy gels from a single checkout, with products shipped from both Amazon fulfillment centers and third-party sellers. GU Original Sports Nutrition Energy Gel 24-Packs, such as the Caramel Macchiato flavor, are available for $48.00. Backcountry.com also sells GU products through Amazon’s marketplace.

GU Energy Labs has been producing gels since 1993, when Dr. Bill Vaughn created the original formula to help his daughter perform better during ultra-marathons. The brand has since become one of the most widely used energy gel lines among endurance athletes.

Amazon Prime members receive free shipping on eligible orders, and many gel products qualify for Subscribe & Save discounts. The platform’s review system lets buyers read feedback from thousands of verified purchasers before committing to a flavor or brand.

The main limitation of Amazon is the lack of single-serving purchases for most products. Gels typically come in boxes of 12 or 24, which makes flavor testing more expensive compared to TheFeed.com’s mix-and-match approach.

GU Energy Labs: Direct From the Original Brand

GU Energy Labs sells directly through its own website, offering the full lineup of original and Roctane energy gels. The Roctane Ultra Endurance Energy Gel is designed for extreme and long-duration activities, packing 100 calories and 1,425mg of amino acids per packet. This formula contains three times the amino acids and twice the sodium found in the original GU Energy Gel.

Buying direct from GU provides access to limited-edition flavors and new product releases before they reach third-party retailers. The brand also runs periodic promotions and loyalty programs for repeat customers.

For athletes committed to GU products, the direct site makes sense. For those who want to compare brands side by side or purchase single servings, TheFeed.com remains the better option.

Key Caffeinated Energy Gel Products to Know

Several gels appear across multiple retailers. Understanding the differences helps athletes choose based on carbohydrate content, caffeine level, and stomach tolerance.

Maurten Gel 100 Caf 100 contains 25g of carbohydrates and 100mg of caffeine, providing approximately 100 kcal per sachet. The Hydrogel Technology allows athletes to consume it without water and with minimal stomach distress. The caffeine content matches about one cup of brewed coffee or 1.5 espressos.

Maurten Gel 160 contains 40g of carbohydrates per sachet, totaling approximately 160 kcal. This higher-carb option suits athletes who prefer fewer gel intakes per hour while still hitting fueling targets.

GU Roctane Ultra Endurance Energy Gel delivers 100 calories per packet with 1,425mg of amino acids. The elevated amino acid and sodium content targets athletes performing at high intensity for multiple hours.

SiS GO Energy + Caffeine provides 22g of carbohydrates and 75mg of caffeine. The isotonic formula absorbs quickly and works well for athletes who have experienced stomach issues with thicker gels. A 150mg caffeine version is also available.

Shipping and Return Policy Comparison

Running Warehouse offers the lowest barrier for free shipping. REI provides the longest return window for members. TheFeed.com delivers the most flexibility for testing new products through single-serving purchases and the Flavor Guarantee.

Which Website Should You Choose?

• TheFeed.com works best for athletes who want to sample multiple brands and flavors before committing to bulk purchases. The single-serving option, combined with the Flavor Guarantee for Feed 1st members, removes the financial risk of buying a box of gels that taste terrible mid-race.
• Running Warehouse suits athletes who prioritize shipping speed and generous return policies over brand selection.
• REI makes sense for existing Co-op members who want to earn rewards on their purchases and appreciate the 365-day return window.
• Amazon offers convenience and competitive pricing for athletes who already know which gels they prefer and want to buy in bulk.
• For caffeinated energy gels specifically, TheFeed.com’s partnership with Science in Sport and its stock of Maurten, GU, and other top brands makes it the most comprehensive single destination.