Sodium thiosulfate (sodium thiosulphate) is an inorganic compound with the formula Na2S2O3.xH2O. Typically it is available as the white or colorless pentahydrate, Na2S2O3·5H2O. The solid is an efflorescent (loses water readily) crystalline substance that dissolves well in water. Sodium thiosulfate is used in gold mining, water treatment, analytical chemistry, the development of silver-based photographic film and prints, and medicine. The medical uses of sodium thiosulfate include treatment of cyanide poisoning and pityriasis. It is on the World Health Organization's List of Essential Medicines, the safest and most effective medicines needed in a health system.

  • Synonyms: Hypo, Sodium Hyposulfite Anhydrous, Sodium Thiosulfate Anhydrous, Sodium Thiosulphate Anhydrous
  • INCI: Sodium Thiosulfate
  • Chemical formula: Na2S2O3
  • CAS #: 7772-98-7
  • Hazard: • May irritate the skin.
    May cause irritation to the eyes.
    May irritate the respiratory tract.
    Reacts with acids to form toxic and irritating sulfur dioxide gas.


Use the links below to view all package sizes for these specific products:

Sodium Thiosulphate 30% Solution
Sodium Thiosulfate 45%
Sodium Thiosulphate Pent GSO


AppearanceClear to white granules or crystals, solid
SolubilitiesSoluble in water
Freezing point48oC (118.4oF)
Molecular weight158.11 g/mol
Weight per gallon10.4 - 11.2 lbs/gal
ClassInorganic Salt, Reducing Agent
GradesIndustrial, USP, Technical


Sodium Thiosulfate uses include Chrome Plating, Cosmetics, Dechlorination Agent, Electroplating, Gel Stabilizer, Leather Tanning, Mordant – Dyes, Oil Field Service Chemicals, Paper & Paperboard, Photographic, Reducing Agent, Shampoo, Textile, Water Treatment o Fixers - used in fixing baths to remove undeveloped silver halide.

Quick Answers

Sodium thiosulfate is an inorganic sodium salt composed of sodium and thiosulfate ions in a 2:1 ratio. It has a role as an antidote to cyanide poisoning, a nephroprotective agent and an antifungal drug.

A reliable source for your chemical compounds is important for your business. It does not matter if you are an independent company that occasionally orders a small quantity of products, or a large manufacturer that consumes large bulk quantities in just-in-time deliveries. In North America, your top choice for sodium thiosulfate is Brenntag.

We combine our global footprint and purchasing power with a localized approach in the U.S. and Canada, thanks to over 190 individual locations spread out across North America. Our proximity enables you timely delivery of your chemicals, and rapid response when you need our help. That is the advantage you receive when buying your sodium thiosulfate from the global market leading distributor.

Sodium thiosulfate is available in pails, metal drums, totes, tank trucks quantities

You can download a copy of the SDS for sodium thiosulfate from Brenntag Connect.

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