This beer claims to be the world strongest beer in the world with an ABV of 67.5%. On Brewver the ABV is not listed as their are some discrepancies.

The beer was released in 2013 for the first time when there was rumor about the ABV of this beer and "Armageddon" from the same brewery. The beers were tested in a laboratory and the result was 22.8% ABV (official: 65% ABV) for Armageddon and 41.1% ABV (official: 67.5% ABV). Later another batch was tested with 67.5% but soon it got official that this was only the reason because pure ethanol was added. Therefore the product is often not seen as real beer.

For further information see e.g. http://thebeercast.com/2014/09/snake-venom-asa.html

Brewery description:
Snake Venom is the world’s strongest beer as of 24 October 2013, coming in at 67.5%. It is dark amber in colour with no carbonation due to the high ABV. Unlike the previous Armageddon, the alcohol is not masked in Snake Venom. It is highly present yet it still tastes like a beer with a good degree of hop profile.

Each batch is tested by the brewery before bottling and random batches are tested externally.