Calcein AM is one the most popular fluorescent probes used for labeling and monitoring cellular functions of live cells. However, the single color of Calcein AM makes it impossible to use this valuable reagent in the multicolor applications. For example, it is impossible to use Calcein AM in combination of GFP-tranfacted cells due to the same color to GFP. To address this color limitation of Calcein AM, we have developed Calcein Orange and Calcein Red. These two new Calcein AM analogs enable the multicolor labeling and functional analysis of live cells in combination with Calcein AM. In addition, we have also developed CytoCalcein Violet 450, CytoCalcein Violet 500, CytoCalcein Blue 550 and CytoCalcein Blue 600 for flow cytometric applications.  CytoCalcein dyes exhibit similar biological properties to Calcein, AM. They are optimized for the excitation wavelengths of a variety of flow cytometers, providing additional colors for flow cytometric analysis of live cells. CytoCalcein Violet 450 and CytoCalcein Violet 500 are well excited by 405 nm of violet laser and emit fluorescence at 450 nm and 500 nm respectively. CytoCalcein Blue 550 and CytoCalcein Blue 550 are well excited by 488 nm of blue laser and emit fluorescence at 550 nm and 600 nm respectively.