In the title molecule, C 9 H 7 N 3 O 3 , the indazole moiety is essentially planar and the mean plane of the acetyl substituent is twisted by 5.3 (1) from its plane. In the crystal, weak C-HÁ Á ÁO and C-HÁ Á ÁN hydrogen bonds form layers parallel to (102), which are associated through -stacking interactions to form a threedimensional network. The structure was refined as a two-component twin. Structure descriptionThe diverse pharmacological properties exhibited by 1H-indazoles have sparked the emergence of novel methods toward their synthesis. Indazole is a frequently found motif in drug substances with important biological activities such as antimicrobial (Li et al., 2003), anti-inflammatory (Lin et al., 2008) and anticancer effects (Zhu et al., 2007). The crystal structure study of the title compound constitutes a continuation of our previous work on indazole derivatives (Mohamed Abdelahi et al., 2017;El Brahmi et al., 2012).The indazole moiety is planar to within 0.0093 (16) Å for (C6) with an r.m.s. deviation from the mean plane of 0.005 Å . The acetyl group is slightly twisted out of the indazole plane, as indicated by the dihedral angle of 5.3 (1) between it and the N2/C8/C9/O1 plane. This orientation may be due in part to the intramolecular C2-H2Á Á ÁO1 hydrogen bond (Table 1 and Fig. 1).In the crystal, the molecules form dimers through pairwise C7-H7Á Á ÁN1 hydrogen bonds which are linked into sheets parallel to (102) by C4-H4Á Á ÁO1 hydrogen bonds (Table 1 and Fig. 2). The sheets stack along the a-axis direction and are associated through head-to-head -stacking interactions (Fig. 3) with centroidÁ Á Ácentroid distances of 3.892 (1) Å .