Choose a 250ml multipack if a smaller can suits your gym bag and the amount you intend to drink; choose a 500ml zero-sugar can if you want more drink per serving, but compare its caffeine separately from its sugar content. Red Bull UK states 80mg caffeine for its 250ml Original can, while Monster UK states 150mg for a 500ml Ultra and Sainsbury’s lists 160mg for that product, so check the exact can before relying on either Ultra figure.
A 250ml can takes up less room than a 500ml can and gives you a smaller amount to drink at one time. Red Bull UK states 80mg caffeine for its 250ml Original; check the label rather than assuming another 250ml variant has the same amount.
Monster Ultra offers a zero-sugar 500ml format, according to Monster UK. Zero sugar does not tell you how much caffeine a can contains: Monster UK states 150mg per can, while Sainsbury’s lists 160mg.
Tesco lists 250ml Red Bull multipacks alongside 500ml Monster Ultra and Relentless Origin multipacks. Decide how many cans you want to store separately from how much you intend to drink in one session.
Start with the amount in one can, then compare caffeine, sugar and the pack format. A larger pack does not change the serving size of each can.
| Priority | What to check | Your needs |
|---|---|---|
| Caffeine per can | Read the amount for the whole can, not just per 100ml. Red Bull UK states 80mg for a 250ml Original; Monster UK states 150mg for a 500ml Ultra, but Sainsbury’s lists 160mg. Check Ultra’s can label for the figure that applies to yours. | I want to account for a can alongside any coffee, tea or pre-workout product I use that day. |
| Sugar and ingredients | Check sugars per can and the ingredients list. Monster UK describes Ultra as zero sugar; Tesco lists 19g sugars per 500ml Relentless Origin can. | A zero-sugar option matters to me, but I still want to check its caffeine. If I have a sweetener preference, I’ll read the ingredients too. |
| Can and pack size | Check both can volume and can count. Tesco lists Red Bull Sugar Free in 250ml multipacks and Monster Ultra and Relentless Origin in 4 × 500ml packs. Confirm that the multipack contains cans rather than bottles. | My bag has room for a can, and I want its volume to match what I plan to drink in one session. |
| Warnings and delivery | Read the product’s caffeine warning and the retailer’s delivery conditions. NHS guidance limits caffeine during pregnancy to 200mg a day from all sources. An announced under-16 sales restriction concerns England and is intended for April 2027, subject to Parliamentary approval. | If I’m buying for someone else, I need to check the can’s warnings and any age checks at delivery rather than assume the same rules apply throughout the UK. |
Monster Ultra is zero sugar, according to Monster UK, but its 500ml can has a separately stated caffeine amount. Monster UK and Sainsbury’s give different figures for that amount.
Read sugar and caffeine as separate label entries, and use the figure on the can you buy.
A per-100ml declaration does not by itself tell you what you will consume from a full can. Tesco lists Relentless Origin at 0.03% caffeine, equivalent to 150mg in its 500ml can; Red Bull UK states 80mg in a 250ml Original can.
Compare milligrams per whole can before choosing between the 250ml and 500ml formats.
Tesco lists Lucozade Energy Original as an 8 × 380ml bottle multipack. It does not meet a can-only requirement.
Check the container type as well as the volume and pack count.
Joybuy product pages for some energy drinks specify age verification on delivery. Separately, the UK Government has announced an under-16 sales restriction intended for England from April 2027, subject to Parliamentary approval; that is not a current UK-wide rule.
Check the retailer’s delivery requirements when ordering and keep the England-specific announcement distinct from rules elsewhere in the UK.
Tesco lists Red Bull Sugar Free in 250ml can multipacks. Red Bull UK gives a caffeine figure for its 250ml Original can, which should not be assumed to apply to Sugar Free.
Monster UK describes Ultra as a zero-sugar 500ml can, and Tesco and Sainsbury’s list 4 × 500ml multipacks.
Tesco lists Relentless Origin as a 4 × 500ml can multipack and states 19g sugars per 500ml can.
Tesco lists Lucozade Energy Original in an 8 × 380ml bottle multipack.
These Joybuy options include compact 250ml cans and larger 500ml cans, with both zero-sugar and other varieties. Compare the label on the exact variant when caffeine or sugar per can determines your choice.
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The 250ml cans provide a compact single-can format for a gym bag. Red Bull UK states 80mg caffeine for a 250ml Original can; check the pack label for the sugar declaration relevant to this purchase.
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This 12-pack is for someone who wants a larger 500ml can rather than a compact 250ml serving. Check the can’s caffeine and sugar declarations for the full amount you intend to drink.
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This four-pack combines a compact 250ml can with a sugar-free variant. Check Sugarfree’s own caffeine declaration rather than applying the figure for Red Bull Original.
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This four-pack suits someone seeking a zero-sugar drink in a larger 500ml can. Monster UK and Sainsbury’s give different caffeine figures for Ultra, so check the declaration on the can before calculating intake.
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This four-pack offers another 500ml can format. Read the can’s caffeine and sugars per serving before comparing it with zero-sugar or smaller-can options.
Compare milligrams in the complete can and account for caffeine from other food and drink that day. Red Bull UK states 80mg in a 250ml Original can; Monster UK states 150mg in a 500ml Ultra, while Sainsbury’s lists 160mg for Ultra, so check its can before using a precise figure.
No: sugar content and caffeine content are separate label checks. Monster UK describes its 500ml Ultra as zero sugar but states 150mg caffeine per can; Sainsbury’s lists 160mg for Ultra, making the can label important when comparing exact amounts.
NHS guidance says not to exceed 200mg caffeine a day during pregnancy, counting caffeine from all food and drink. Check the amount in the complete can alongside other sources, and follow the product’s pregnancy warning.
The UK Government’s announced under-16 sales restriction is intended for England from April 2027, subject to Parliamentary approval; it should not be treated as a current UK-wide ban. A retailer may separately require age verification for delivery, so check its conditions when ordering.