
Listen guys, unless you have a huge surplus of pants hangers, Q-tips, dental floss and whatever weird detritus that’s often recommended, a lot of so-called “lifehacks” – those hobo techniques for saving money and/or accomplishing some inane task with “readily available” household objects – are a bit impractical, if they even work at all.
But there’s one, at least, that seems like it could perfectly epitomize the intended convenience of the lifehack: Testing the freshness of eggs by just dropping them into a cup of water. We’ve all got water and a cup on hand and, so long as you’re a sentient human being and not, like, a family dog reading this on your owner’s tablet after you taught yourself English.
But does this egg trick really work? Impressed at having actually found a real, potentially useful lifehack, we took it upon ourselves to test it out. Here’s what we found.
First, let’s cover the basic idea behind this lifehack. According to multiple sources, eggs of varying freshness will float to various different degrees in a cup of water. The freshest of eggs will apparently sink down and land sideways on the bottom of a glass, while eggs of moderate freshness will sort of half-stand, half-sink, and a stale egg will stand on end at the bottom of a glass. A totally bad egg will, the wisdom goes, float at the surface of the water.
Like so:
While we’ve seen videos and commentary on the Internet that this method objectively does not work, the American Department of Agriculture apparently enthusiastically endorses it as a bulletproof test of egg freshness. Well, what better outlet to put the debate to bed than a random Asia news website, we thought.
Arming ourselves with a calendar (so you know we’re not cheating), and a pair of eggs – one completely fresh and one a few days past its best-by date, we set to work. We plunked our eggs into two cups of tap water and, lo and behold, the old egg did, in fact, float to the surface.
We found the effect to be even more pronounced when we used salt water, as the slightly increased buoyancy made the old egg really bob exaggeratedly to the surface.

The official explanation, apparently, for this phenomenon is that air pockets in the eggs expand as the eggs get older, making them more buoyant and smelly.
Go figure. We had always assumed that old eggs float because the now fully-formed embryo inside was doing its best to tread water.
Photos/Vine ©RocketNews24
[ Read in Japanese ]







Got a bunch of old rice lying around? Let us show you how to revive it!
We brave the should-be-abomination of raw egg and coffee, is it a taste sensation? 【Taste Test】
We tried a Japanese egg steamer to achieve the perfect breakfast eggs without a stove
The Osaka taste sensation that no one in Osaka has ever heard of: Coffee & Raw Egg 【Taste Test】
Does the Shirotama Maker kitchen gadget really create perfect instant ramen eggs?
Tokyo subway installing new ticket gates that don’t accept payment through Suica or other IC cards
New Shinkansen luggage drop-off system begins in Japan, making train travel even easier
99-year-old woman rescued while attempting to climb Mt. Fuji
Which country’s foreign tourists spend the most money per-person in Japan? Hint: Not the U..S. or China
Starbucks Japan adds a new summer Frappuccino to the menu, but is it as refreshing as it looks?
Kodama Shinkansen trains on popular Japan route get a whole new look this winter
Foreign hiker on Mt. Fuji loses consciousness and dies, becoming climbing season’s second fatality
Starbucks Japan releases a miniature display rack so you can create your very own store at home
Eight great words for talking about summer in Japan in Japanese
Studio Ghibli releases anime T-shirts that pay homage to one of Hayao Miyazaki’s most personal films
Japan now has human refrigerators inspired by Japanese vending machines
Hatsune Miku collaborates with Hokusai’s art in new Vocaloid ukiyo-e illustration series [Pics]
Japanese convenience store releases Japanese convenience store-flavor fried chicken
Family Mart’s new Tokyo flagship convenience store doesn’t feel convenient, but is that a problem?
Starbucks Japan releases new Discovery Series collection celebrating local regions and traditions
Teen girl in Japan refuses to be victim, personally escorts train pervert to police for arrest
Is Japan’s tourism boom slowing down? Foreign visitor numbers fall for first time in five years
Starbucks Japan releases exclusive new Bearista collection…with beary cute details
Studio Ghibli has a new anime out, and there’s only one place in the world where you can see it
Japan announces sudden 400-percent increase in visa fees for foreigners entering the country
Salomon releases Japan-exclusive Mt. Fuji hiking gear that doubles as an amazing souvenir
Japan triples departure tax, foreign tourists and locals now must pay more to leave country
Japan launches first overnight Shinkansen bullet train between Tokyo and Osaka this summer
Family Mart opens new “Famima” flagship store in Tokyo that’s like a tourist attraction
Japan’s human washing machines will go on sale to general public, demos to be held in Tokyo
Starbucks Japan releases new drinkware and goods for Valentine’s Day
Starbucks Japan releases new sakura goods and drinkware for cherry blossom season 2026
Japan’s newest Shinkansen has no seats…or passengers [Video]
Japanese ninja certification exam attracts 131 candidates from Japan and abroad
Put sesame oil in your coffee? Japanese maker says it’s the best way to start your day【Taste test】
Japan reportedly adding Japanese language skill requirement to most common foreigner work visa
Can this cushion really protect an egg from being sat on? How about a few punches?
These rare eggs cost more than a typical meal in Japan but are they really that special?
We found the prettiest TKG ever at a restaurant specializing in raw eggs on rice in Tokyo
The internet’s latest culinary masterpiece: Cup Noodle Steamed Egg【Taste Test】
Creepy creatures from the seabed that you can eat!【Taste Test】
Jellied Eggs, Pleasing to the Eye and Good for the Skin
Does this egg timer from Japanese 100-yen store Daiso really work?
How to turn your leftover instant ramen broth into delicious chawanmushi Japanese egg custard
Can instant TKG from Don Quijote really recreate Japan’s beloved raw-egg-on-rice dish?
7-Eleven Japan’s egg broth and rice may be the dream combination we’ve been missing【SoraKitchen】
Which Japanese convenience store has the best onsen tamago hot spring eggs?
Restaurant specializing in tamago kake men (TKM), raw egg over noodles, opens in central Tokyo
We try Dom Dom Burger’s new limited-time-only Spicy Cod Roe Thick Egg Omelet Burger
Testing Japan’s sold-online love potion: Mr. Sato makes his coworkers drink the romantic mixture
Ramen egg showdown! Which Japanese convenience store makes the best nitamago?【Taste test】
We taste-test the new chicken nugget French fry Cup Noodle【SoraNews24 taste test】