There's nothing worth anything in there. There's nothing of value in there. There's nothing valuable in there.

#1: replace "worth" with "of worth". After you change this, #1 has the same meaning as #2. #2 and #3 do not have the same meaning. My shoes have value, but they are not valuable. A gold watch has value and is also valuable. Something is only valuable if it has a *great deal* of value.

No, "There's nothing worth in there." is incorrect. However, these two sentences are correct and can be used interchangeably in most cases: ✅ "There's nothing of value in there."
✅ "There's nothing valuable in there." Difference: * "Nothing of value" → sounds a bit more formal or neutral. * "Nothing valuable" → more common in everyday speech. To fix the first sentence, you could say:
🔹 "There's nothing worth keeping in there."
🔹 "There's nothing worth looking at in there." ("Worth" must be followed by a noun or gerund—e.g., "worth keeping", "worth seeing".)

Yes, they can be used interchangeably if you correct the first sentence. I suggest saying "there's nothing worth much in there" (informal, but not slang) or "there's nothing of worth in there" (a bit formal, but neither very formal nor informal). Your last two phrases (containing "of value" and "valuable") are a bit formal also.

The last two sentences are correct. The first sentence is almost correct. It needs the preposition "of" before "worth". "There´s nothing of worth in there." But, I would typically add in the word "any" before "worth." It just sounds better to me: "There´s nothing of any worth in there."