Herbs short-lived perennial or annual, 15--40 cm tall. Stems caespitose or simple, suberect; sterile stems decumbent; flowering stems pilose and/or glandular pubescent all round. Basal leaves ovate, obovate-lanceolate, ovate-spatulate, or spatulate, 5--13 × 3--10 mm, both surfaces pilose, base attenuate into a petiole; cauline leaves subsessile, ovate, oblong, or narrowly ovate-oblong, 1--3(--4) × 0.3--1(--1.2) cm, both surfaces pilose or pubescent, margin densely ciliate, apex acute. Cyme terminal, spreading, lax, up to 40-flowered; bracts leaflike, ovate, 3--5 mm, both surfaces glandular pubescent. Pedicel slender, 0.5--2.5 cm, densely glandular pubescent, recurved after anthesis. Sepals oblong-or ovate-lanceolate, 5--6 mm, abaxially densely glandular pubescent, margin membranous or narrowly so. Petals obovate or obovate-oblong, shorter than to 2 × as long as sepals, apex 2-lobed. Stamens shorter than petals. Ovary ovoid, ca. 2 mm. Styles 5, linear, slightly longer than ovary. Capsule cylindric, 8--10 mm, ca. 2 × as long as calyx, 10-toothed, teeth usually recurved. Seeds brown, usually 0.4--0.8 mm in diam., tuberculate. Fl. Apr--Jun, fr. May--Jul.
Perennial, often with short tufted non-flowering axillary branches. Flowering stems ascending to erect, (5)-15-45-(60) cm tall, with dense spreading eglandular hairs. Lvs ovate, lanceolate, elliptic or oblanceolate, (5)-10-25-(50) × 3-10-(20) mm, the lower petiolate, the upper sessile, with eglandular hairs. Infl. crowded; infructescence lax; fruiting pedicels usually > sepals, with dense eglandular hairs. Bracts ovate, the lower without scarious margins, eglandular hairy on both surfaces, the upper with scarious margins, glabrous above. Sepals scarious on margins, 4-6 mm long, glabrous above, with eglandular hairs on green part beneath; hairs not overtopping apex. Petals c. = sepals. Styles 1.5-2 mm long. Capsule cylindric, 2× length of calyx. Seeds c. 0.6 mm long, tuberculate.
For description of subspecies occurring in Australia see Cerastium fontanum subsp. fontanum.