How to Choose an Energy Gel: A Runner's Buying Guide

An energy gel is concentrated sugar in a sachet, 21 to 90 g of carbohydrate depending on which one you pick up. Six label numbers decide whether it is the right one for you: carbs per packet, carb source, caffeine, sodium, whether it needs water, and what 25 g of carbohydrate costs. The table below carries all six for 29 gels sold in the US and UK, from the official labels.

Read a gel label in twenty seconds

• Carbs per packet. 21 to 90 g across the table, most standard gels 22 to 30 g. That number decides how many you carry, so read it first.
• Carb source. Look for fructose next to the glucose or maltodextrin. Glucose alone is burned at about 1.0 g per minute, a glucose-fructose mix at about 1.75, measured in trained cyclists (Jentjens and Jeukendrup, 2005). Whether fructose is in there matters more than the exact ratio brands advertise.
• Caffeine. Eight of the 29 carry it, 30 to 100 mg. Doses that reliably help endurance are 3 to 6 mg per kg of body mass, so a 60 kg runner is looking at 180 to 360 mg (Guest et al., 2021).
• Sodium. 0 to 250 mg per packet, and it is a tiebreaker rather than a strategy. Eleven athletes lost roughly 1,565 mg of sodium during 90 minutes of moderate cycling in 30-degree heat (Baker et al., 2019), which even the 250 mg gel at the top of that column will not replace. Work out your own losses with the electrolyte calculator.
• Water. The labels disagree: 10 say none is needed, 10 say it is required or recommended, and 9 say nothing at all. Settle it before race day: it decides where on the course you can take a gel.
• Cost per 25 g of carbs. Not the sticker price. Carbs Fuel Original and GU Energy Gel both list at $2.00, but one delivers 50 g of carbohydrate and the other 23 g.

Five formats, and the two that surprise people

Products group by how they are made, and that sets both packet size and the water question.

Format	Carbs per packet	Water on the label	Who it suits
Standard gel	21-50 g, plus one 90 g pouch	Required, recommended or unstated; the two PF 30 gels say not needed	Most runners. The three cheapest rows in the table are all standard gels.
Isotonic gel	22-30 g	Not needed, on all four	Runners who want to skip the aid station, at a weight cost.
Hydrogel	25-40 g	Not needed, on all three	Neutral taste and an easy swallow. Holds the most expensive row in the table.
Chews	36 g per pack	Not stated	Anyone who wants to dose in small bites. Slow to chew at race pace.
Real-food alternative	26-28 g	One says not needed, one says nothing	Long, slow efforts where sweet syrup stops going down.

Not needing water has a weight. High5 Energy Gel Aqua carries 23 g of carbohydrate in a 66 g packet; GU Energy Gel carries the same 23 g in 32 g. Isotonic gels are pre-diluted, so you carry the water either way, in your pocket instead of at the aid station.

The hydrogel case is thinner than the price implies. A meta-analysis of seven studies found no difference in performance, carbohydrate oxidation or blood glucose when sodium alginate was added to a carbohydrate drink (Sutehall et al., 2022). In runners, adding pectin and alginate did not lift carbohydrate oxidation above 1.1 g per minute (Barber et al., 2020). One trial points the other way.

The hydrogel evidence, including the study that disagrees

Sutehall et al. (2022) pooled seven studies against an isocaloric control and found no separation on performance, carbohydrate oxidation or blood glucose, with zero heterogeneity between studies. Their own caveat matters: several of the trials were not intense enough to provoke gut problems in the first place, so “no difference” is not the same as “disproved at race intensity”. King et al. (2020) went at the marketing claim of faster stomach emptying with less distress and reported that gut-distress ratings did not differ, while concluding that hydrogels come out similar to traditional carbohydrate sources.

The exception is Rowe et al. (2022): 11 trained male runners taking 90 g of carbohydrate per hour ran a time trial 2.1% faster on hydrogel, with fewer gut symptoms. It has not been repeated, and it sits in exactly the high-intake, high-intensity gap the meta-analysis flags. It may turn out to be right, but it is not settled, and what is doing the work in the packet either way is the glucose and fructose.

Energy gel spec table — grouped by type, not ranked

Every gel in our database that you can buy in the US or UK, sorted by type and listed alphabetically inside each group. There is no ranking: the last two columns are arithmetic on the official label, so you can see what a packet actually delivers and what 25 g of carbohydrate costs.

Product	Packet	Carbs	Density	Caffeine	Sodium	Water?	Per packet (USD / GBP)	Per 25 g carbs (USD)
Standard gels Concentrated syrup in a tear-top sachet. Whether it wants water depends on the label, so read the water column.
Carbs Fuel Caffeinated Original 50g Energy Gel maltodextrin, sucrose, fructose · 2:1	—	50 g	—	100 mg	105 mg	Advised	$2.5 / —	$1.25
Carbs Fuel Original 50g Energy Gel maltodextrin, sucrose, fructose · 2:1	—	50 g	—	0	105 mg	Advised	$2 / —	$1
GU Energy Liquid Energy maltodextrin, fructose	—	24 g	—	0	74.8 mg	Advised	$2.5 / —	$2.6
GU Energy Original Energy Gel maltodextrin, fructose	32 g	23 g	72%	0	60 mg	Advised	$2 / —	$2.17
GU Energy Original Energy Gel (caffeinated flavours) maltodextrin, fructose	32 g	23 g	72%	40 mg	60 mg	Advised	$2 / —	$2.17
GU Energy Roctane Energy Gel maltodextrin, fructose	32 g	21 g	66%	35 mg	125 mg	Advised	$3 / —	$3.57
Hammer Nutrition Hammer Gel maltodextrin, fruit juice concentrate, rice syrup	33 g	22 g	67%	0	25 mg	—	$1.46 / —	$1.66
HIGH5 Energy Gel Caffeine glucose syrup, maltodextrin	40 g	23 g	57%	30 mg	16 mg	—	— / £1.45	—
Huma Chia Energy Gel - Original fruit puree, cane sugar, brown rice syrup, chia seed · 2:1	43 g	24 g	56%	0	105 mg	Yes	$2.5 / —	$2.6
Huma Chia Energy Gel PLUS (double electrolytes) fruit juice concentrate, brown rice syrup, fruit puree, chia seed · 2:1	42 g	24 g	57%	0	240 mg	Yes	$2.75 / —	$2.86
Naak BOOST Gel 30 - Salted Lemon agave powder, dehydrated tapioca syrup, dextrose · 2:1	48 g	30 g	63%	0	250 mg	—	— / —	—
Precision Fuel & Hydration PF 30 Caffeine Gel maltodextrin, fructose · 2:1	51 g	30 g	59%	100 mg	0 mg	No	— / £3.16	—
Precision Fuel & Hydration PF 30 Gel maltodextrin, fructose · 2:1	51 g	30 g	59%	0	0 mg	No	— / £2.37	—
Precision Fuel & Hydration PF 90 Gel maltodextrin, fructose · 2:1	153 g	90 g	59%	0	0 mg	—	— / £5	—
Science in Sport Beta Fuel Energy Gel maltodextrin, fructose · 1:0.8	—	40 g	—	0	12 mg	—	— / £2.33	—
STYRKR GEL50 Dual-Carb Energy Gel maltodextrin, fructose · 1:0.8	72 g	50 g	69%	0	0 mg	—	— / £2.5	—
TORQ TORQ Caffeine Energy Gel (Guarana) maltodextrin, fructose · 2:1	45 g	29 g	64%	89 mg	49 mg	Yes	— / £2.4	—
TORQ TORQ Energy Gel maltodextrin, fructose · 2:1	45 g	29 g	64%	0	49 mg	Yes	— / £2.2	—
Veloforte Primo - Natural Energy Gel fruit juice (glucose and fructose), beetroot	33 g	22 g	67%	0	110 mg	—	— / £2.17	—
Isotonic gels Diluted to roughly blood concentration so the brand says no water is needed. Bigger, heavier packets for the same carbs.
HIGH5 Energy Gel Aqua glucose syrup, maltodextrin, fruit juice concentrate	66 g	23 g	35%	0	28 mg	No	— / £1.42	—
Neversecond C30 Energy Gel maltodextrin, fructose · 2:1	—	30 g	—	0	200 mg	No	$3.5 / —	$2.92
Neversecond C30+ Caffeine Energy Gel maltodextrin, fructose · 2:1	—	30 g	—	75 mg	200 mg	No	$3.5 / —	$2.92
Science in Sport GO Isotonic Energy Gel maltodextrin (single source)	—	22 g	—	0	4 mg	No	— / £1.75	—
Hydrogels Pectin and alginate form a gel in the stomach. Same carbs per packet as a standard gel; the evidence for easier digestion is mixed.
Maurten Gel 100 glucose, fructose · 1:0.8	40 g	25 g	63%	0	20 mg	No	$3.75 / £2.83	$3.75
Maurten Gel 100 CAF 100 glucose, fructose · 1:0.8	40 g	25 g	63%	100 mg	22 mg	No	$4.33 / £3.38	$4.33
Maurten Gel 160 glucose, fructose · 1:0.8	65 g	40 g	62%	0	30 mg	No	$4.58 / £3.75	$2.86
Chews Solid gummies you chew. Slower to eat on the run, easier to portion.
Skratch Labs Energy Chews Sport Fuel sugar, glucose syrup	50 g	36 g	72%	0	90 mg	—	$2.75 / —	$1.91
Real-food alternatives Rice cakes, waffles, yokan and similar. Carbs come with fat or protein, so digestion is slower.
Spring Energy Awesome Sauce (Cinnamon Apple Pie Gel, Vegan) apple juice, basmati rice, apple sauce, maple syrup	60 g	28 g	47%	0	45 mg	No	$4.2 / —	$3.75
UnTapped Maple UnTapped Athletic Fuel organic pure Vermont maple syrup	38 g	26 g	68%	0	5 mg	—	$2.49 / —	$2.39

Packet weight, carbohydrate, caffeine and sodium are copied from each brand's official label. Carb density = carbs ÷ packet weight. Price is the list price per packet at the official store or a named retailer on the date shown; per-25-g cost = price ÷ carbs × 25. 29 products · labels and prices checked 2026-09-08.

How this table is built (and why nothing is ranked)

Rows are grouped by how the product is made, then alphabetical by brand. No product gets a score, because the right gel depends on your stomach, your race length and your budget, not on a leaderboard.

• Carb density (carbs ÷ packet weight) tells you how much of what you carry is fuel. A 25 g-carb hydrogel in a 40 g packet is 63%; the same carbs in a 60 g isotonic packet is 42%.
• Per 25 g carbs normalises price to the amount of fuel you actually need, so a 45 g-carb gel that costs twice as much can still be the cheaper fuel.
• Prices are list prices at the official store where it sells direct, otherwise at a named retailer, on the date shown. Sale prices are ignored. Currency conversions are never applied.

RunDida earns no commission on any product in this table. Links go to the brand's own product page and are marked nofollow.

What the table shows once you sort it

List prices checked in September 2026: 17 of the 29 have a US price and 14 a UK price. The per-25 g column is worked out from the dollar price, so the UK-only rows are blank there; divide the pound price by the carbs and multiply by 25 yourself.

• The five cheapest per 25 g of carbohydrate. Carbs Fuel Original ($1.00), Carbs Fuel Caffeinated ($1.25), Hammer Gel ($1.66), Skratch energy chews ($1.91) and GU Energy Gel ($2.17). Maurten Gel 100 CAF 100 sits at the far end at $4.33.
• The bigger packet is the cheaper fuel, even inside one brand. Maurten Gel 160 comes to $2.86 per 25 g of carbohydrate against $3.75 for Gel 100.
• Carb density runs from 35% to 72%. That column tells you how much of what you are carrying is fuel rather than water.
• Sodium is not why you buy a gel. Näak Boost Gel 30 tops the table at 250 mg; Styrkr Gel50 and all three Precision Fuel gels (PF 30, PF 30 Caffeine, PF 90) are 0 mg, because Precision Fuel sells electrolytes separately.

Pick by your situation

• Marathon. Beyond 2.5 hours the ceiling rises to about 90 g of carbohydrate per hour, and reaching it needs a mixed glucose-fructose formula (Burke et al., 2011), so check the carb source before the brand. How many packets that comes to is the gel calculator; when to take them is the race fuelling strategy guide.
• Half marathon. Under 2.5 hours the target is 30 to 60 g of carbohydrate per hour (Burke et al., 2011), so a two-hour half is two to four packets. Buy for how easily it goes down, and put the effort into the days before with the carb loading calculator.
• Sensitive stomach. Buy a mixed pack rather than a box of one thing, because a gel you have not run with is not a gel you have tested. In a 25-runner trial, the group that took gels at race intake through two weeks of training cut its gut symptoms by around 60%, while the placebo group did not improve (Costa, Miall et al., 2017); the marathon nutrition guide covers how.
• You could not swallow it late last time. That is a different problem from your stomach, and carb density is where you look: 35% means the packet is mostly water, 72% means it is mostly syrup. Runners who hit this switch to isotonic or thinner gels for the closing hour.
• You want caffeine. The three 100 mg entries are Maurten Gel 100 CAF 100, Precision Fuel PF 30 Caffeine and Carbs Fuel Caffeinated; the other five sit between 30 and 89 mg. The effective range is 3 to 6 mg per kg (Guest et al., 2021), and race-morning coffee counts toward it.
• Budget. The habit that quietly costs the most is training on cheap gels and racing on an expensive one, which makes race day the first time you use it. If the race-day gel is too dear to train with, it is the wrong race-day gel.
• HYROX and hybrid races. Packet size and mess matter more than the last 5 g of carbohydrate when you carry it through sled pushes, and the HYROX hub covers event-specific preparation.

Check these before you pay

• The caffeinated version looks almost identical. Some brands sell caffeine as a flavour rather than a separate product, so with GU the dose follows the flavour in your hand. Read the flavour name, not just the brand.
• Check what your race hands out. In 2026 Boston puts Maurten Gel 100 and Gel 100 CAF 100 on course at three points, Berlin gives Gel 100 at 27.5 km, and London hands out Lucozade Sport Gels at miles 13 and 19. If that is your race, train on it: a course gel you have never used is still a new gel.
• A label is a claim, not a measurement. Third-party tests in 2024 found Spring Energy Awesome Sauce carried 30% to 38% of the carbohydrate on its label, the brand traced it to its own rice-cooking and applesauce process, reformulated, and now lists 28 g in a 60 g pouch where the old label claimed 45 g in 54 g. The testing was crowdfunded, and Maurten, a competitor, was among the donors.
• Clif Shot is gone. Clif no longer lists an energy gel in its catalogue, so any roundup still recommending one is out of date. Its chews are still sold: 24 g of carbohydrate per three-piece 30 g serving, which is 48 g in a full 60 g packet — printed in the Nutrition Facts image on each product page, which is why roundups keep missing it.
• Match the water column to the course. If your gel needs water and the aid stations are 5 km apart, that is a plan rather than a detail. The hydration calculator gives you the volume, and the hydration guide covers sweat sodium.
• Buy singles before boxes. The most upvoted answer to “which gel should I buy” in running communities is a refusal to answer: one runner says Huma works best for them, then adds that this means nothing for you. A mixed pack settles that in a way no review can.