5-Nitro-1-benzofuran-2(3H)-one

In the crystal structure of the title compound, C8H5NO4, essentially planar molecules [largest deviation from the least-squares plane = 0.030 (2) ] form stacks along the a-axis direction. Intercentroid separations between overlapping benzene rings within the stack are 3.6594 (12) and 3.8131 (12) . Molecules from neighboring stacks are linked by weak C—H...O hydrogen bonds into inversion dimers.