An embeddable corrosion rate meter (ECRM) for detecting and measuring corrosion in metal and concrete structures comprises an electrochemical cell with an ECRM sensor circuit (20). Circuit (20) includes at least one working electrode (10) evenly spaced from counter/reference electrode (12) with the separation distance between the electrodes determining an electrolyte medium resistance. Circuit (20) also includes a current source generated by power source (28) connected through different resistances RI (26) to Rn (24). A first selector is used in applying current through each or the plurality of resistances to working electrode (10) and a second selector (16) selects a duration of the current pulse. Current is applied between the electrodes through galvanostat (22) and polarization of working electrode (10) is measured by voltmeter/A-D converter (18) connected via link (34). The voltmeter has an input impedance greater than a billion ohms. An external reader-head with power link (32) powers circuit (20) and reads and transfers corrosion measurement data via data link (36) to computer (30).