ABSTRACT: Present approach is an effort to develop a handy, less in cost, less power consuming and compact, colorimeter for quantitative colorimetry with diminished detector size. A relatively small electric current with improved power sensitivity photosensitive device: MORICA MP series-MH-208 photodiode has been used to diminish size of the assembled colorimeter. This detector has good signal to noise ratio and hence can sense very low level of intensity. The major challenge in assembling these portable analytical devices is to reduce detector size. Common photo resistor or other newly electronic component including silicon photodiodes can be used as detector in portable colorimeters. In the recent colorimeters, output current is amplified by connecting the detectors to operational amplifiers. Although the reports in the literature reveal a great deal of advances on colorimeters, still efforts are needed for simplifying the colorimeter for analytical applications in field conditions for estimation of various analytes. The standard chemical solution, ranging between 2.5 to 80 mg/dl of Copper Sulphate in distilled water, was determined at 650nm wavelength of light by using self-designed colorimeter and the commercial Perkin-Elmer Spectrophotometer in correspondence of Beer-Lambert law. Both were compared for the calibration of self-designed colorimeter. A good Linearity in sensor output of the self-designed colorimeter was recorded. . A comparative study has been done for glucose estimation in blood in between a selfdesigned colorimeter and a strip-based commercial glucometer. A self-designed colorimeter was able to detect glucose using a very small amount 10µl of blood serum sample and could detect glucose in the range of 50 to 600 mg/dL. The Coefficient of variation for selfdesigned colorimeter was determined to be 4.171 % in comparison to16.671% (for a stripbased commercial glucometer).