An extract from Table 3.1 of BS EN 1992-1-1 is shown below. Eurocode practise is to use Cylinder Strength for concrete, instead of Cube Strength which was used in previous British Standards. Cylinders are tests using a sample with an aspect ratio of 2:1, instead of the cube same of aspect ratio 1:1. Therefore, for the same type of concrete a cube sample will suggest a higher concrete strength, this is reflected in the below table.

C25/30C30/37C35/45C40/50C45/55C50/60C55/67C60/75C70/85Equation
$$f_{ck}$$ 253035404550556070-
$$f_{ck,cube}$$303745505560677585-
$$f_{cm}$$333843485358636878$$f_{cm} = f_{ck} +8 \text{ MPa}$$
$$f_{ctm}$$2.62.93.23.53.84.14.24.44.6$$f_{ctm} = 0.3 \times f_{ck}^{2/3} \leq C50/60$$
$$f_{ctm} = 2.12 \ln (1+(f_{ck}/10)) > C50/60$$
$$f_{ctk,0.05}$$1.822.22.52.72.933.13.2$$f_{ctk,0.05} = 0.7 \times f_{ctm} { MPa}$$
$$f_{ctk,0.95}$$3.33.84.24.64.95.35.55.76$$f_{ctk,0.95} = 1.3 \times f_{ctm} { MPa}$$
$$E_{cm}$$310003300034000350003600037000380003900041000$$E_{cm} = 22,000 [ f_{cm}/10]^{0.3}\text{ } f_{cm} \text{ in MPa}$$
$$\varepsilon_{c1} (^0\!\!/\!_{00})$$2.12.22.252.32.42.452.52.62.7$$\varepsilon_{c1} (^0\!\!/\!_{00}) = 0.7 f_{cm}^{0.31}\leq 2.8$$
$$\varepsilon_{cu1} (^0\!\!/\!_{00})$$3.53.53.53.53.53.53.232.8$$\varepsilon_{cu1} (^0\!\!/\!_{00}) = 2.8+27[(98-f_{cm})/100]^4 > C50/60$$
$$\varepsilon_{c2} (^0\!\!/\!_{00})$$2222222.22.32.4$$\varepsilon_{c2} (^0\!\!/\!_{00}) = 2.0+0.085(f_{ck}-50)^{0.53} > C50/60$$
$$\varepsilon_{cu2} (^0\!\!/\!_{00})$$3.53.53.53.53.53.53.12.92.7$$\varepsilon_{cu2} (^0\!\!/\!_{00}) = 2.6+35[(90-f_{ck})/100]^4 > C50/60$$
$$n$$2222221.751.61.45$$n = 1.4+23.4[(90-f_{ck})/100]^4 > C50/60$$
$$\varepsilon_{c3} (^0\!\!/\!_{00})$$1.751.751.751.751.751.751.81.92$$\varepsilon_{c3} (^0\!\!/\!_{00}) = 1.75+0.55[(f_{ck}-50)/40] > C50/60$$
$$\varepsilon_{cu3} (^0\!\!/\!_{00})$$3.53.53.53.53.53.53.12.92.7$$\varepsilon_{cu3} (^0\!\!/\!_{00}) = 2.6+35[(90-f_{ck})/100]^4 > C50/60$$