C9H8O4

The molecular formula C₉H₈O₄ (molar mass: 180.15 g/mol, exact mass: 180.0423 u) may refer to:

• Acetozone
• Aspirin
• 4-Hydroxyphenylpyruvic acid, a natural phenol
• Dihydroxycinnamic acids:
• Caffeic acid (3,4-Dihydroxycinnamic acid)
• Umbellic acid (2,4-dihydroxycinnamic acid)
• 2,3-Dihydroxycinnamic acid
• 2,5-Dihydroxycinnamic acid
• 3,5-Dihydroxycinnamic acid
• Homophthalic acid
• Monomethyl phthalate
• Uvitic acid