Hydrogel optical fiber random laser

•Based on the dye-doped hydrogel material, a low-threshold flexible film as well as a fiber random laser were realized.•Both random lasers in this paper can tune the wavelength of the random laser under the condition of changing the temperature.•Both hydrogel films and fiber random lasers have excellent flexibility and mechanical toughness, and the threshold of random lasers can be reduced by bending or stretching them.