ACI Quick Reference

Compressive strength f′c (psi)

Existing tool range: 2,000–12,000 psi.

Concrete density wc (pcf)

Normalweight calculation path (≥ 140 pcf)

Ec §19.2.2.1

3,604,997 psi

fr §19.2.3.1

0.474 ksi

λ §19.2.4

1.00

Ec = 57,000√f′c (ACI 318-14 §19.2.2.1b, normalweight)

fr = 7.5λ√f′c (ACI 318-14 §19.2.3.1)

Compatibility note: the displayed result preserves the legacy no-λ calculation.

Scroll horizontally to inspect all reinforcing-bar properties.

ASTM standard reinforcing bar properties
Bar	dia (in)	Area (in²)	Wt (lb/ft)	Std Bend — inside r		Tie Bend — inside r
Bar	dia (in)	Area (in²)	Wt (lb/ft)	in	out in	in	out in
#3	0.375	0.110	0.376	1.125	1.500	0.750	1.125
#4	0.500	0.200	0.668	1.500	2.000	1.000	1.500
#5	0.625	0.310	1.043	1.875	2.500	1.250	1.875
#6	0.750	0.440	1.502	2.250	3.000	2.250	3.000
#7	0.875	0.600	2.044	2.625	3.500	2.625	3.500
#8	1.000	0.790	2.670	3.000	4.000	3.000	4.000
#9	1.128	1.000	3.400	4.512	5.640	—	—
#10	1.270	1.270	4.303	5.080	6.350	—	—
#11	1.410	1.560	5.313	5.640	7.050	—	—
#14	1.693	2.250	7.650	8.465	10.158	—	—
#18	2.257	4.000	13.600	11.285	13.542	—	—

Target As (in²/ft)

Existing tool range: 0.1–6.0 in²/ft.

insufficient (< 1.0×)
meets target (1.0–< 1.5×)
exceeds target (1.5–< 2.0×)
excessive (≥ 2.0×)

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Reinforcement area per foot by bar size and spacing
s (in)
4.0	0.330 , insufficient	0.600 , insufficient	0.930 , exceeds target	1.320 , excessive	1.800 , excessive	2.370 , excessive	3.000 , excessive	3.810 , excessive	4.680 , excessive
4.5	0.293 , insufficient	0.533 , insufficient	0.827 , meets target	1.173 , exceeds target	1.600 , excessive	2.107 , excessive	2.667 , excessive	3.387 , excessive	4.160 , excessive
5.0	0.264 , insufficient	0.480 , insufficient	0.744 , meets target	1.056 , exceeds target	1.440 , excessive	1.896 , excessive	2.400 , excessive	3.048 , excessive	3.744 , excessive
5.5	0.240 , insufficient	0.436 , insufficient	0.676 , meets target	0.960 , exceeds target	1.309 , excessive	1.724 , excessive	2.182 , excessive	2.771 , excessive	3.404 , excessive
6.0	0.220 , insufficient	0.400 , insufficient	0.620 , meets target	0.880 , meets target	1.200 , exceeds target	1.580 , excessive	2.000 , excessive	2.540 , excessive	3.120 , excessive
6.5	0.203 , insufficient	0.369 , insufficient	0.572 , insufficient	0.812 , meets target	1.108 , exceeds target	1.458 , excessive	1.846 , excessive	2.345 , excessive	2.880 , excessive
7.0	0.189 , insufficient	0.343 , insufficient	0.531 , insufficient	0.754 , meets target	1.029 , exceeds target	1.354 , excessive	1.714 , excessive	2.177 , excessive	2.674 , excessive
7.5	0.176 , insufficient	0.320 , insufficient	0.496 , insufficient	0.704 , meets target	0.960 , exceeds target	1.264 , excessive	1.600 , excessive	2.032 , excessive	2.496 , excessive
8.0	0.165 , insufficient	0.300 , insufficient	0.465 , insufficient	0.660 , meets target	0.900 , meets target	1.185 , exceeds target	1.500 , excessive	1.905 , excessive	2.340 , excessive
8.5	0.155 , insufficient	0.282 , insufficient	0.438 , insufficient	0.621 , meets target	0.847 , meets target	1.115 , exceeds target	1.412 , excessive	1.793 , excessive	2.202 , excessive
9.0	0.147 , insufficient	0.267 , insufficient	0.413 , insufficient	0.587 , insufficient	0.800 , meets target	1.053 , exceeds target	1.333 , excessive	1.693 , excessive	2.080 , excessive
9.5	0.139 , insufficient	0.253 , insufficient	0.392 , insufficient	0.556 , insufficient	0.758 , meets target	0.998 , exceeds target	1.263 , excessive	1.604 , excessive	1.971 , excessive
10.0	0.132 , insufficient	0.240 , insufficient	0.372 , insufficient	0.528 , insufficient	0.720 , meets target	0.948 , exceeds target	1.200 , exceeds target	1.524 , excessive	1.872 , excessive
10.5	0.126 , insufficient	0.229 , insufficient	0.354 , insufficient	0.503 , insufficient	0.686 , meets target	0.903 , meets target	1.143 , exceeds target	1.451 , excessive	1.783 , excessive
11.0	0.120 , insufficient	0.218 , insufficient	0.338 , insufficient	0.480 , insufficient	0.655 , meets target	0.862 , meets target	1.091 , exceeds target	1.385 , excessive	1.702 , excessive
11.5	0.115 , insufficient	0.209 , insufficient	0.323 , insufficient	0.459 , insufficient	0.626 , meets target	0.824 , meets target	1.043 , exceeds target	1.325 , excessive	1.628 , excessive
12.0	0.110 , insufficient	0.200 , insufficient	0.310 , insufficient	0.440 , insufficient	0.600 , insufficient	0.790 , meets target	1.000 , exceeds target	1.270 , excessive	1.560 , excessive
12.5	0.106 , insufficient	0.192 , insufficient	0.298 , insufficient	0.422 , insufficient	0.576 , insufficient	0.758 , meets target	0.960 , exceeds target	1.219 , exceeds target	1.498 , excessive
13.0	0.102 , insufficient	0.185 , insufficient	0.286 , insufficient	0.406 , insufficient	0.554 , insufficient	0.729 , meets target	0.923 , meets target	1.172 , exceeds target	1.440 , excessive
13.5	0.098 , insufficient	0.178 , insufficient	0.276 , insufficient	0.391 , insufficient	0.533 , insufficient	0.702 , meets target	0.889 , meets target	1.129 , exceeds target	1.387 , excessive
14.0	0.094 , insufficient	0.171 , insufficient	0.266 , insufficient	0.377 , insufficient	0.514 , insufficient	0.677 , meets target	0.857 , meets target	1.089 , exceeds target	1.337 , excessive
14.5	0.091 , insufficient	0.166 , insufficient	0.257 , insufficient	0.364 , insufficient	0.497 , insufficient	0.654 , meets target	0.828 , meets target	1.051 , exceeds target	1.291 , excessive
15.0	0.088 , insufficient	0.160 , insufficient	0.248 , insufficient	0.352 , insufficient	0.480 , insufficient	0.632 , meets target	0.800 , meets target	1.016 , exceeds target	1.248 , excessive
15.5	0.085 , insufficient	0.155 , insufficient	0.240 , insufficient	0.341 , insufficient	0.465 , insufficient	0.612 , insufficient	0.774 , meets target	0.983 , exceeds target	1.208 , exceeds target
16.0	0.083 , insufficient	0.150 , insufficient	0.232 , insufficient	0.330 , insufficient	0.450 , insufficient	0.593 , insufficient	0.750 , meets target	0.953 , exceeds target	1.170 , exceeds target
16.5	0.080 , insufficient	0.145 , insufficient	0.225 , insufficient	0.320 , insufficient	0.436 , insufficient	0.575 , insufficient	0.727 , meets target	0.924 , meets target	1.135 , exceeds target
17.0	0.078 , insufficient	0.141 , insufficient	0.219 , insufficient	0.311 , insufficient	0.424 , insufficient	0.558 , insufficient	0.706 , meets target	0.896 , meets target	1.101 , exceeds target
17.5	0.075 , insufficient	0.137 , insufficient	0.213 , insufficient	0.302 , insufficient	0.411 , insufficient	0.542 , insufficient	0.686 , meets target	0.871 , meets target	1.070 , exceeds target
18.0	0.073 , insufficient	0.133 , insufficient	0.207 , insufficient	0.293 , insufficient	0.400 , insufficient	0.527 , insufficient	0.667 , meets target	0.847 , meets target	1.040 , exceeds target

As = (bar area × 12) / spacing.

ACI Quick Reference

Concrete Properties — ACI 318-14

ASTM Standard Reinforcing Bars

As per ft — Spacing Table (in²/ft)