Everyone knows that sea water tastes salty. But not everyone knows that the amount of salt in different seas and oceans, as well as the chemical composition of the saline solution, varies significantly.
In some seas there is relatively little salt, in others, on the contrary, the water is saltier than usual.
How is sea salinity measured?
In order to find out which sea has the saltiest water, scientists, of course, do not taste it while traveling through different seas of the planet. Everything is much simpler: the salinity of sea water is measured by determining how much salt is contained in one liter of water. To do this, you just need to evaporate the water and weigh the remaining salt.
If we do this experiment with ordinary tap water, we will get about 1.5 - 2 grams of salts in the dry residue, which give the taste. Distilled water, which does not contain salts, is absolutely tasteless, unlike ordinary drinking water.
Sea salt, obtained by evaporating sea water, consists not only of table salt, known to everyone, but also of a large number of other salts and minerals: sulfates, bicarbonates, borates, etc. In fact, almost the entire periodic table of elements can be found in sea water.
About 80 seas and oceans are marked on the map of our planet, and in each of them the salt concentration is at its own level. Moreover, different parts of the same sea have different salinity: where a large river flows into the sea, it decreases sharply. The Baltic Sea is the least salty in the world: the amount of salt in a liter of its water barely reaches 7 grams.
The saltiest sea on the planet
Sometimes in popular literature there is a statement that the Dead Sea is considered the saltiest in the world. In fact, this is not true, and here's why: The Dead Sea is not actually a sea, but a lake. 
It is not connected to the World Ocean by any strait, river or canal, therefore, from a geographical point of view, it is a lake. Therefore, in terms of salinity level, it should be compared with other salty lakes on the planet, and not with the seas.
In fact, the Red Sea is the saltiest, with water containing about 41 grams of salt for every liter. This is a very high figure that the waters of the Red Sea were able to achieve due to the hot, arid climate of the shores. Not a single river flows into it; the level of the Red Sea is replenished only due to the flow of water from the Gulf of Aden.
The evaporation of water is very high, and the incoming less salty water does not have time to dilute the brine. The neighboring Mediterranean Sea, to which the Red Sea is connected via the Suez Canal, has a salinity of only about 26 grams per liter of water.
The waters of the Red Sea are striking in their purity and transparency, since not a single river flows into it, bringing with it river silt and fine sand. Despite the rather serious depth (about 3 kilometers in the deepest part), it is well warmed up by the sun's rays, and even in winter its temperature does not fall below 20 degrees, and in summer it stays at 27-28 degrees. 
These are ideal conditions for the reproduction of numerous marine fish, animals, shellfish and other underwater life. The underwater world of the Red Sea is extremely rich and diverse, despite the high salinity of the water.
The saltiest seas in Russia
The most saline sea washing the shores of Russia is the Barents Sea, the salt content of which reaches 35 grams per liter of water. It is located in the northern part of the country, so in winter it is almost completely covered with ice. Only a small area of the sea in the southwestern part remains free.
Even in summer, the water temperature does not exceed 12 degrees Celsius. Despite this, the Barents Sea is rich in fish, among which there are many commercial species - perch, herring, capelin, catfish, beluga, etc. 
The other northern seas of Russia are slightly inferior in salinity to the Barents, but are also among the top ten most saline seas in the world. These are the Laptev Sea (34 grams of salt per liter), the Chukchi Sea (33 grams of salt per liter) and the White Sea (30 grams of salt per liter of water).
There are about 80 seas on the planet. Some of them are so salty that drowning in their water is almost impossible. Below are the top 10 such seas.
Our rating opens with the White Sea, which washes the borders of the Russian Federation. The salinity in this sea sometimes reaches about 30‰ (ppm), that is, there are 30 grams of salt per liter of water. Although the sea is salty, it is home to approximately 50 species of fish.
Chukchi Sea (33‰)
Another “our” sea. The salinity of the Chukchi Sea is 33‰, which is what allows it, as well as the White and other seas, not to freeze in severe frosts (down to -1.8 degrees). The sea stretches between Chukotka and Alaska. Here you can find many species of fish, as well as walruses and seals.
Laptev Sea (34‰)
Another sea washing our borders. The salinity of the Laptev Sea is slightly higher than that of the Chukchi Sea - 34‰. The reservoir is located between Severnaya Zemlya and the New Siberian Islands. All year round, sea water rarely warms up above zero. Fish species such as sturgeon and perch are found here, and walruses are among the animals.
Barents Sea (35‰)
The next sea is again slightly saltier than the previous one - 35‰. Officially, this sea is recognized as the saltiest in Russia. In winter, the southwestern part of the reservoir freezes, the rest does not. The underwater world of the Barents Sea is incredibly rich - here you can find not only whales and killer whales, but also a great variety of different species of fish: from herring to perch.
Sea of Japan (35‰)
This sea is not inferior in salinity to the Barents. The Sea of Japan partially washes the island of Sakhalin, as well as the islands of Japan and the shores of Eurasia. In the southern part, the sea warms up to 26 degrees Celsius, and therefore it can even be called a “resort”. An incredible amount of living creatures live in the Sea of Japan: there is simply no counting of seafood and fish here.
Ionian Sea (38‰)
One of the most picturesque and clean seas in the world is also very salty. This sea is the densest and saltiest in Greece. In addition to the picturesque underwater world, the Ionian Sea boasts a temperature: in the summer, the water warms up to 26-28 degrees. The sea is very popular among tourists.
Aegean Sea (38.5‰)
Almost the same characteristics will apply to the Aegean Sea. Doctors advise washing with fresh water after swimming in this sea, because such a high concentration of sodium can negatively affect the skin. Greece and the Balkans swim in this sea. A myriad of living creatures live in it, including octopuses, sponges and fish.
Mediterranean Sea (39.5‰)
The Mediterranean Sea, located between Europe and Africa, is very salty in places – 39.5‰. Along the shores where tourists relax, such salinity is not observed; it is concentrated in other parts of the reservoir. The Mediterranean Sea is one of the most diverse in its animal world - 500 species of fish, hundreds of shellfish and a lot of seafood. And this is not the limit.
Red Sea (42‰)
Another border sea, but this time between Africa and Asia. The Red Sea is one of the saltiest in the world, but this does not interfere with its inhabitants - stunning corals, various fish, dolphins, mollusks and crustaceans. The water in the sea mixes all year round - in winter, the upper layers cool and sink to the bottom, and the warm ones rise up. By the way, the sea is incredibly clear.
Dead Sea (270‰)
The absolute champion of our rating. Located on the border of Israel and Jordan, the Dead Sea is striking in its salinity - about 200 grams of salt per 1 liter of water (270‰). This sea is fundamentally different in its chemical composition from all others on Earth: 50% of it consists of magnesium chloride, and it also contains a lot of calcium, bromine, potassium and other mineral elements.
Potassium salts from the Dead Sea water are crystallized artificially, and the density of the reservoir is so high that it is simply impossible to drown in it. Among other things, there is healing mud in the sea. Sometimes the water in the sea heats up to 40 degrees, which accelerates evaporation. And most importantly, there is no underwater world in the Dead Sea; with such salinity, it is impossible to live in it. That's why it's Dead.
Rating of seas by salinity
There are about 80 seas on our planet. Of course, the Dead Sea would take first place in the ranking, since its waters are famous for their salinity. The Dead Sea is one of the saltiest bodies of water on Earth, salinity is 300-310 ‰, in some years up to 350 ‰. But scientists call this body of water a lake.
- Red Sea with a salinity of 42‰.
The Red Sea is located between the shores of Africa and Asia. In addition to its salinity and warmth, the Red Sea can boast of its transparency. Many tourists love to relax on its shores.
2. The Mediterranean Sea has a salinity of 39.5‰.
The Mediterranean Sea washes the shores of Europe and Africa. In addition to salinity, it can also boast of its warm waters - in summer they warm up to 25 degrees above zero.
3. Aegean Sea with a salinity of 38.5‰.
The waters of this sea with a high concentration of sodium can cause skin irritation. Therefore, after swimming it is better to take a fresh shower. In summer, the water warms up to 24 degrees Celsius. Its waters wash the shores of the Balkan Peninsula, Asia Minor and the island of Crete.
4. Ionian Sea with a salinity of 38 ‰.
This is the densest and saltiest Greek sea. Its waters allow slow swimmers to hone this skill, as the high density will help keep the body afloat. The area of the Ionian Sea is 169 thousand square kilometers. It washes the shores of Southern Italy, Albania and Greece.
5. The Sea of Japan, whose salinity is 35‰
The sea is located between the continent of Eurasia and the Japanese islands. Its waters also wash the island of Sakhalin. The water temperature depends on the geographical location: in the north – 0 -+12 degrees, in the south – 17-26 degrees. The area of the Sea of Japan is more than 1 million square kilometers.
6. Barents Sea with salinity 34.7-35 ‰
This is the marginal sea of the Arctic Ocean. It washes the shores of Russia and Norway.
7. Laptev Sea with a salinity of 34‰.
Area - 662 thousand square kilometers. It is located between the New Siberian Islands and Severnaya Zemlya. The average annual water temperature is 0 degrees Celsius.
8. Chukchi Sea with a salinity of 33‰.
In winter, the salinity of this sea rises to 33‰, while in summer the salinity decreases slightly. The Chukchi Sea has an area of 589.6 thousand km². The average temperature in summer is 12 degrees Celsius, and in winter - almost 2 degrees Celsius.
9. White Sea also has high salinity. In the surface layers the figure stopped at 26 percent, but at depth it increases to 31 percent.
10. Laptev Sea. Salinity at the surface is recorded at 28 percent
The sea has a harsh climate with temperatures below 0°C for more than nine months of the year, sparse flora and fauna, and low population along the coast. Most of the time, with the exception of August and September, it is under ice. The salinity of sea water at the surface in the northwestern part of the sea in winter is 34 ‰ (ppm), in the southern part - up to 20-25 ‰, decreasing in summer to 30-32 ‰ and 5-10 ‰, respectively. The salinity of surface waters is strongly influenced by the melting of ice and the runoff of Siberian rivers.
In the section on the question, help with the rating of sea salinity given by the author Staff the best answer is According to personal feelings - Mediterranean, more salty Aegean, the saltiest - Red. Then - Dead. And % - you need to look...
Salinity is the amount of solids in grams dissolved in 1 kg of sea water, provided that all halogens are replaced by an equivalent amount of chlorine, all carbonates are converted to oxides, and organic matter is burned.
It is measured in “‰” (“ppm”).
The average salinity of the world's oceans is 35 ‰. To calibrate instruments, so-called normal water with a salinity close to 35 ‰ is extracted from the Bay of Biscay.
Baltic - 7-8
Azovskoe - 12
Black - 16
Mramornoe 26
Adriatic - 35-38
Aegei 37
Ligurian -38
Mediterranean (overall) about 38 - 39.5
Red - 39-40
Dead 260-270
Source Wikipedia and:
Reply from Neurologist[guru]
Aegean Sea
Salinity 37.0-39.00/00.
Mediterranean Sea
Large evaporation leads to a strong increase in salinity. Its values increase from 3. to V. from 36 to - 39.5. The density of water on the surface varies from 1.023-1.027 g/cm³ in summer to 1.027-1.029 g/cm³ in winter.
Red Sea
Strong evaporation of warm water turned the Red Sea into one of the saltiest on the globe: 38-42 grams of salts per liter. Salinity - 40-60 g/l. Salt content reaches up to 40‰
Dead Sea
The content of minerals in water reaches 33%, an average of 28% (for comparison in the Mediterranean Sea - 4%).
Barents Sea
The salinity of the surface layer of water in the open sea throughout the year is 34.7-35.0‰ in the southwest, 33.0-34.0‰ in the east, and 32.0-33.0‰ in the north. In the coastal strip of the sea in spring and summer, salinity drops to 30-32 ‰, and by the end of winter it increases to 34.0-34.5 ‰.
Sea of Azov
The salinity of the sea before the regulation of the Don was three times less than the average salinity of the ocean. Its value on the surface varied from 1 ppm at the mouth of the Don to 10.5 ppm in the central part of the sea and 11.5 ppm near the Kerch Strait. After the creation of the Tsimlyansky hydroelectric complex, the salinity of the sea began to increase (up to 13 ppm in the central part). Average seasonal fluctuations in salinity rarely reach 1-2 percent.
Davis Sea
Salinity 33.0-33.5‰.
Baltic Sea
The salinity of sea water decreases from the Danish Straits, connecting the Baltic Sea with the salty North Sea, to the east. In the Denmark Straits, salinity is 20 ppm at the surface of the sea and 30 ppm at the bottom. Towards the center of the sea, salinity decreases to 6-8 ppm at the sea surface, in the north of the Gulf of Bothnia it drops to 2-3 ppm, in the Gulf of Finland to 2 ppm. Salinity increases with depth, reaching 13 ppm in the center of the sea near the bottom.
White Sea
The large influx of river water and insignificant exchange with the Barents Sea led to a relatively low salinity of the surface waters of the sea (26 ppm and below). The salinity of deep waters is much higher - up to 31 ppm.
Conducted site monitoring! Phew! Chocolate for you! !
Reply from luxury[guru]
For me, the Dead is the saltiest. And then Ionian, Aegean, Mediterranean.
The Earth can be confidently called a water planet, because the World Ocean surrounding the land covers 71% of its entire surface. , included in its composition, differ from each other in many ways. Including such a parameter as salinity, which means the amount of salts dissolved in one liter of water under certain conditions. The salinity of sea water is most often measured in “‰” (ppm). Now it won’t be difficult to find out which is the saltiest sea on Earth.
5. Ionian Sea - salinity exceeds 38 ‰
The Ionian Sea is the part of the Mediterranean that washes the shores of southern Italy and Greece. The bottom of the sea is covered with silt, and closer to the shores - with sand and small shell rock. Its area is 169 thousand km², maximum depth is 5,121 m. This is the greatest depth in the entire Mediterranean Sea. Commercial fishing of mackerel, mullet, tuna, and flounder is carried out. The waters of the Ionian Sea are safe and very warm, even in February their temperature does not fall below 14°C, and at the peak of the holiday season, in August, reaches 25.5°C. Among its inhabitants are bottlenose dolphins, huge turtles, and octopuses. And very dangerous sea urchins and white sharks can hardly be found near the coast. Poisonous dragon fish, which can cause an allergic reaction in humans, are more active at night and burrow into the sand during the day.
4. Aegean Sea - salinity from 37 to 40.0 ‰
This semi-enclosed sea has about 20,000 islands and is located in the eastern Mediterranean. The total area is 179 thousand km². Through the straits it is connected to the Marmara, Black and Mediterranean seas. The salinity of its waters is increasing, which is associated with global warming. After swimming, it is recommended to rinse off the sea water, as this can negatively affect the condition of the skin and mucous membrane of the eyes. There is a fishing industry in the Aegean Sea; sponges are actively mined and octopuses are caught. Due to the fact that there is little plankton in this sea, fishing in its waters is gradually declining.
3. Ligurian Sea - salinity 38 ‰
This sea is located in the western part of the Mediterranean. The shores are steep and rocky, but there are sandy beaches. Many small rivers flow into the Ligurian Sea, which originate in the Apennines. On its shores there are such important ports as:
- Limpia, which is considered the sea gate of Nice.
- Cruise ports of Savona, La Spezia, with container and bulk terminals.
- Genoese port, ranking first in terms of trade volume in Italy.
Despite the high salinity of these waters, on the French-Italian coast of the Ligurian Sea is located one of the most famous resort areas in the world - the Riviera.
2. Mediterranean Sea - salinity from 36 to 39.5 ‰
The Mediterranean Sea is a relic of the ancient Tethys Ocean. It is considered one of the largest seas in size, its area is 2.5 million km². Its basin includes the Sea of Azov, Black and Marmara. The salinity of the sea fluctuates significantly, as water with a much lower salinity enters from the Atlantic through the Strait of Gibraltar. The amount of zooplankton in the Mediterranean Sea is relatively small, and as a result there are few different species of fish, as well as marine animals and mammals. But algae are present in large numbers, especially peridinea and diatoms. The bottom fauna is very poor due to yellowish silt, which is not conducive to the development of life. There are 550 species of fish in the Mediterranean Sea, 70 of which are endemic. The most common species are: mackerel, sardine, horse mackerel, mullet, etc. There are also larger “inhabitants” - sharks, rays, tuna. Edible shellfish are common.
1. Red Sea - salinity 41 ‰
The saltiest of all, the Red Sea is located in a tectonic depression, the depth of which can reach 3 km. It is an inland sea of the Indian Ocean. The hot climate, which provokes strong surface evaporation and low precipitation (about 100 mm per year), and the absence of rivers flowing into the sea, leads to a gradual increase in its salinity. Due to the absence of silt and sand, which are abundant in river water, the Red Sea is distinguished by its extraordinary transparency and purity. The water temperature even in winter is +20 °C, and in summer it is much higher.
Despite its salinity, the waters of the Red Sea amaze with the huge number of different species of fish living in it. But ichthyologists believe that only 60% of fish capable of existing at great depths have been discovered. The sea is extremely beautiful, and it has many interesting and sometimes funny inhabitants, but touching them is strictly prohibited. Corals, sponges, jellyfish, as well as sea urchins, moray eels and poisonous sea snakes are potentially extremely dangerous. Any contact with them can result in a burn, significant blood loss or a severe allergic reaction, and sometimes death. 44 species of sharks live in warm sea waters. The most terrible of them is the tiger, which can easily attack a person.
Having examined them separately, it is now easy to conclude which is the saltiest sea. The salinity of the very famous Dead Sea reaches 350 ‰, but in fact, despite its name, it is an endorheic lake that is gradually drying up.
