A handheld, pen-like colorimeter for measuring the color of an object is provided. The invention includes three light sensors, each of which detects a separate primary color. A microprocessor in the colorimeter calculates a single composite color value from the three separate color measurements from the light sensors and then compares the composite color value with a list of color values, wherein each value corresponds to a unique color name. The colorimeter selects the color name that matches the composite color value of the object presents the color name to a user, using a liquid crystal display (LCD) or an audio speaker. Another embodiment of the present invention uses lasers emitting primary colors, rather than passive light sensors. The lasers shine on an object one at a time, and the reflected laser light from the three lasers is detected by a special light sensor. The three color measurements are then combined to produce a composite value, similar to the first embodiment.