This study reports the development of calcium alginate-based highly mesoporous carbon spheres (AMCS). These materials exhibit significant potential in chromatographic applications and demonstrated similar efficiency to commercially available porous graphitic carbon (PGC) and are superior to Starbon® materials in separation of polar carbohydrate analytes. The AMCS exhibit a narrow particle size distribution, are highly spherical and exhibit extensive mesoporous networks (up to ca. 90% mesoporosity). It is shown how calcium content can significantly influence the textural properties of the resulting AMCS materials. The AMCS production process requires no additional templating agents and temperatures of only 800 °C. In contrast, PGC are manufactured through an energy-intensive manufacture process, which requires a hard-templated mesoporous carbon intermediate to be pyrolysed to over 2000 °C under argon. Thus AMCS demonstrate promise as a green alternative to PGC in chromatographic applications.