Concrete compositions have a fine-to-coarse aggregate ratio optimized for increased workability with minimal segregation and bleeding. The concrete compositions include at least water, cement, coarse aggregate, and fine aggregate and have a slump of at least 1 inch and a 28-day compressive strength of at least about 1500 psi. Workability is improved by minimizing the viscosity as a function of the aggregate content, while minimizing segregation and bleeding. To improve workability, the concrete compositions include between 45% and 65% fine aggregate and between 35% and 55% coarse aggregate as a function of total aggregate volume. For relatively low strength concrete (1500-4500 psi), the fine aggregate is 55-65% of the total aggregate volume. For medium strength concrete (4500-8000 psi), the fine aggregate is 50-60% of the total aggregate volume. For high strength concrete (>8000 psi), the fine aggregate is 45-55% of the total aggregate volume. Overall workability can be maintained or improved even if slump is decreased.