UK · Soft drinks
How much caffeine is in Diet Coke?
Coca-Cola Great Britain lists 46 mg in a 330 ml can of Diet Coke.
Diet Coke: UK can, bottle and caffeine-free options
A standard UK 330 ml can contains 46 mg. The calculated concentration is about 13.9 mg per 100 ml; 500 ml of the same formulation would contain about 69.7 mg. Use the amount consumed rather than counting every container as one can.
Diet Coke No Caffeine is a separate product. Standard Diet Coke contains caffeine despite containing no sugar. Coca-Cola Original Taste lists 34 mg per 330 ml, compared with Diet Coke’s 46 mg.
Manufacturer’s Diet Coke and No Caffeine product information · Compare UK cola servings · Inspect a documented caffeine-free alternative
A practical next step
Looking for a lower-caffeine alternative?
Coca-Cola Zero Sugar Zero Caffeine is recorded at 0 mg for 330 ml can, compared with 46 mg for the selected Diet Coke serving.
This compares named servings, not necessarily equal volumes, taste or nutrition. Verified source record. Official Great Britain announcement for the zero-caffeine variant, including the 330 ml can format.
Compare these listed servings →Browse manufacturer-identified caffeine-free UK fizzy drinks or choose another documented swap.
Interactive serving
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Where this figure comes from
- Source type
- Manufacturer
- Market
- UK
- How we got the amount
- Manufacturer listed
- Source reviewed
- 23 October 2026
Great Britain FAQ and serving size.
Estimated caffeine remaining over time
These figures apply CaffCalc’s exponential model to the adjusted 46.0 mg starting value. They are calculations, not measurements of caffeine in a particular person.
| Hours elapsed | 3-hour half-life | 5-hour half-life | 7-hour half-life |
|---|---|---|---|
| 0 | 46.0 mg | 46.0 mg | 46.0 mg |
| 3 | 23.0 mg | 30.3 mg | 34.2 mg |
| 5 | 14.5 mg | 23.0 mg | 28.0 mg |
| 8 | 7.2 mg | 15.2 mg | 20.8 mg |
| 10 | 4.6 mg | 11.5 mg | 17.1 mg |
| 12 | 2.9 mg | 8.7 mg | 14.0 mg |
With the central five-hour model, the estimate falls below 25 mg after approximately 4.4 hours. The faster and slower columns show why one fixed clearance time shouldn’t be treated as a personal fact.
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