The optical behavior of a simple intramolecular charge transfer (ICT) fluorescent probe 1 has been described to detect cyanide (CN⁻) selectively for the first time in solution and living cells. The strong emission displayed by 1 is attributed to a decrease in ICT from anthracene to dicyanovinyl group. The change in color of the solution was visible to the naked eye. Probe 1 forms a 1:1 adduct with CN⁻ with detection limit of 26 ppb.