Bittersweet vs semisweet chocolate

Legally, nothing — they share a floor in the US standards. In practice, whichever a maker calls the less sweet end of their own range.

Why these get confused

Readers assume bittersweet is a defined step darker than semisweet. It is the same legal category under a different name, and one company's bittersweet may be sweeter than another's semisweet.

Side by side

 BittersweetSemisweetWhy it matters
Legal minimum35% chocolate liquor under the US standards.The same 35%, from the same standard.There is no legal boundary between them at all. The distinction is a manufacturer's marketing decision.
Typical cacao contentUsually 60–85%.Usually 50–65%.The convention holds within a maker's range and not across makers. The printed percentage is the only reliable guide.
What recipes assumeA darker, less sweet chocolate; common in more serious American baking.Around 55–60%; the default for cookies and anything involving chips.A European reader substituting a 70% bar for 'semisweet' removes roughly twelve percentage points of sugar.
Outside the USUsed loosely as a synonym for dark chocolate.Used loosely as a synonym for dark chocolate.Neither word is a standardised name in the EU, where 'chocolate' is the defined term.

Choose Bittersweet when

When you want the darker end of a maker's range, or when a recipe specifies it and prints a percentage you can check.

Choose Semisweet when

When following an American recipe that says only 'semisweet', which is assuming around 55–60%.

When the distinction does not matter

Substituting one for the other in most bakes. The difference between them is generally smaller than the difference between either and a 70% European bar.

Related

Compared in

Sources

  • ChocolateHQ editorial synthesisChocolateHQ(citation identity confirmed; passage not re-read)
  • 21 CFR Part 163 — Cacao ProductsUnited States Food and Drug Administration(citation identity confirmed; passage not re-read)