Anchor Bolt Size Chart: F1554 Capacity & Loads 2026

The bolt’s steel is only half the anchorage

An anchor bolt has two jobs: the steel has to hold the load, and the concrete has to hold the bolt. This page answers the first one — the steel tensile capacity from ASTM F1554 — and it does not answer the second: concrete breakout, pullout and pryout (ACI 318) govern the anchorage and are NOT covered here, and embedment, edge distance and spacing decide the real allowable load. On the defaults — diameter 3/4 in, grade 36, load 10,000 lbf — the stress area is 0.3340 in², the minimum tensile capacity is 19,372 lbf, the maximum tensile capacity is 26,720 lbf, the yield load is 12,024 lbf, the utilization is 51.62% and the verdict is PASS — the smallest diameter that carries 10,000 lbf at Grade 36 is 5/8 in (13,108 lbf).

Anchor bolt size chart — ASTM F1554, minimum tensile load (lbf)

Every cell is the exact formula value — stress area × minimum tensile strength, half-up to the whole lbf — never hand-typed. ASTM F1554 Table 2 publishes the same loads rounded to the nearest 100 lbf: the 3/4-in Grade 36 cell is 19,400 lbf published, our exact value is 19,372 lbf. At the defaults — diameter 3/4 in, grade 36, load 10,000 lbf — the stress area is 0.3340 in², the minimum tensile capacity is 19,372 lbf, the maximum tensile capacity is 26,720 lbf, the yield load is 12,024 lbf, the utilization is 51.62% and the verdict is PASS. Check the identities: minimum tensile capacity = stress area × minimum tensile strength; maximum tensile capacity = stress area × maximum tensile strength; yield load = stress area × minimum yield strength; utilization = required load ÷ minimum capacity × 100; smallest diameter = the first diameter whose minimum capacity carries the load. Rounding convention: totals are computed from unrounded values, so rounded parts may differ by a cent from their rounded sum.

The worked example, line by line

Setup: diameter 3/4 in, grade 36, load 10,000 lbf.

Line 1 — the stress area. The 3/4-in bolt has a tensile stress area of 0.3340 in² — the area of the threaded section, from ASTM F1554 Table 2 — and 10 threads per inch.

Line 2 — the minimum tensile capacity. 0.3340 in² × 58 ksi = 19,372 lbf. Grade 36 steel is guaranteed to 58 ksi minimum, so the bolt is guaranteed to 19,372 lbf in tension.

Line 3 — the maximum tensile capacity. 0.3340 in² × 80 ksi = 26,720 lbf — the top of the Grade 36 range; the steel will not be stronger than this.

Line 4 — the yield load. 0.3340 in² × 36 ksi = 12,024 lbf — the load where the bolt starts to stretch permanently.

Line 5 — the utilization and the verdict. 10,000 ÷ 19,372 × 100 = 51.62% — the load is inside the minimum capacity, so the verdict is PASS. The smallest bolt that carries 10,000 lbf at Grade 36 is 5/8 in (13,108 lbf).

Reverse: the load for exactly 100% utilization is 19,372 lbf; at 19,371 lbf the utilization is 99.99% (PASS), at 19,373 lbf it is 100.01% (FAIL). The smallest diameter for a 30,000 lbf load at Grade 36 is 1 in; 7/8 in carries only 26,796 lbf (short by 3,204 lbf), 1 in carries 35,148 lbf. The grade for a 25,000 lbf load at 3/4 in is Grade 55; Grade 36 carries only 19,372 lbf (short by 5,628 lbf), Grade 55 carries 25,050 lbf (margin 50 lbf). The load at the yield point is 12,024 lbf; at 12,023 lbf the bolt is below yield, at 12,025 lbf it is above yield. The smallest diameter for a 100,000 lbf load at Grade 105 is 1-1/4 in; 1-1/8 in carries only 95,375 lbf (short by 4,625 lbf), 1-1/4 in carries 121,125 lbf. The maximum tensile capacity at the defaults is 26,720 lbf.

Every branch, checked

Diameter 1 in: Area 0.6060 in², min cap 35,148 lbf, max cap 48,480 lbf, yield 21,816 lbf, utilization 28.45%, PASS, smallest 5/8 in. A bigger bolt carries more — the minimum capacity rises to 35,148 lbf and the utilization falls to 28.45%.

Grade 55: Area 0.3340 in², min cap 25,050 lbf, max cap 31,730 lbf, yield 18,370 lbf, utilization 39.92%, PASS, smallest 1/2 in. The same 3/4-in bolt in Grade 55 carries 25,050 lbf — and the smallest bolt for 10,000 lbf drops to 1/2 in.

Grade 105: Area 0.3340 in², min cap 41,750 lbf, max cap 50,100 lbf, yield 35,070 lbf, utilization 23.95%, PASS, smallest 1/2 in. Grade 105 more than doubles the capacity to 41,750 lbf — but it is limited to 3 in maximum, and the anchorage still governs.

Load 20,000 lbf: Area 0.3340 in², min cap 19,372 lbf, max cap 26,720 lbf, yield 12,024 lbf, utilization 103.24%, FAIL, smallest 7/8 in. Ask the 3/4-in Grade 36 bolt for 20,000 lbf and it fails at 103.24% — step up to 7/8 in, which carries 26,796 lbf.

Load 5,000 lbf: Area 0.3340 in², min cap 19,372 lbf, max cap 26,720 lbf, yield 12,024 lbf, utilization 25.81%, PASS, smallest 1/2 in. A 5,000 lbf load is a quarter of the capacity — the smallest bolt is 1/2 in.

Diameter 2 in + Grade 105: Area 2.5000 in², min cap 312,500 lbf, max cap 375,000 lbf, yield 262,500 lbf, utilization 3.20%, PASS, smallest 1/2 in. The biggest bolt in the table at the strongest grade carries 312,500 lbf — a 10,000 lbf load is only 3.20% of it.

What the defaults assume

The model assumes ASTM F1554 Table 2 tensile stress areas and UNC threads, and the minimum tensile and yield strengths for each grade — it does not model the anchorage: concrete breakout, pullout and pryout (ACI 318) govern the anchorage and are NOT covered, and embedment, edge distance and spacing decide the real allowable load. It assumes the load is pure tension on the bolt — it does not model shear, combined tension and shear, or fatigue. With a 0 lbf load the utilization is 0.00%, the verdict is PASS and the smallest diameter is 1/2 in (the smallest in the table). With a 400,000 lbf load at Grade 36 the smallest diameter is none — the largest bolt in the table (2 in, 145,000 lbf) cannot carry it; at the model level there is no diameter that ties, and the page states the “none” verdict explicitly. Grade 105 is limited to 3 in maximum (our table stops at 2 in). Rounding convention: totals are computed from unrounded values, so rounded parts may differ by a cent from their rounded sum; the reverses are nearest-value solutions, and the exact unrounded figures (19,372, 26,796, 19,372, 12,024, 95,375, 26,720) are stated wherever the rounded figures appear.

Output · formula · meaning

Who uses this

• The contractor sizing a base plate: they learn a 3/4-in Grade 36 bolt holds 19,372 lbf — and they check the 20,000 lbf branch (103.24% FAIL) to see the size where it stops holding.
• The engineer checking a 25,000 lbf uplift: they learn Grade 36 falls short by 5,628 lbf — and they check the Grade 55 branch (25,050 lbf) to see the grade that carries it.
• The designer with a 100,000 lbf load: they learn the smallest Grade 105 bolt is 1-1/4 in — and they check the 2-in + Grade 105 branch (312,500 lbf) to see the top of the table.
• The inspector checking a 1/2-in bolt: they learn it holds 8,230 lbf at Grade 36 — and they check the 1-in branch (35,148 lbf) to see how fast capacity grows with diameter.

Accuracy & limitations

The math is first-principles ASTM F1554: minimum tensile capacity = stress area × minimum tensile strength; maximum tensile capacity = stress area × maximum tensile strength; yield load = stress area × minimum yield strength; utilization = required load ÷ minimum capacity × 100. Every table cell is derived from the area × strength formula — the 3/4-in Grade 36 cell is 0.3340 × 58,000 = 19,372 lbf, not the 19,400 lbf ASTM publishes rounded to the nearest 100. The 4-decimal exact is shown where the rounding matters: the load for exactly 100% utilization is 19,372 lbf; at 19,371 lbf the utilization is 99.99% (PASS), at 19,373 lbf it is 100.01% (FAIL). What the model cannot do is design the anchorage: concrete breakout, pullout and pryout (ACI 318) govern the anchorage and are NOT covered; embedment, edge distance and spacing decide the real allowable load; a licensed engineer must design the anchorage. For the wire that runs to the anchor, see the electrical wire size chart and the wire gauge chart; for another construction reference table, see the dryer vent length chart. This is a calculator, not an engineering opinion.