Load securement calculator
Enter the article's length and weight, whether it's blocked, and your straps or chains. You get the tie-downs required by the federal rules and a WLL check.
By Gustavo · Updated October 2026
TIE-DOWNS REQUIRED
- Minimum by length (393.110)
- 4
- Aggregate WLL needed (50%)
- 6,000 lb
- Your aggregate WLL
- 16,000 lb
Every load we bring you comes with the securement it needs listed up front, so you're never short at the shipper.
How it is calculated
- Minimum count under 49 CFR 393.110:
- Blocked against forward movement: 1 tie-down per 10 ft of length, or part of it.
- Not blocked, 5 ft or less and 1,100 lb or less: 1.
- Not blocked, up to 10 ft: 2.
- Not blocked, over 10 ft: 2, plus 1 for each extra 10 ft or part of it.
- WLL needed under 49 CFR 393.106: total working load limit of at least half the article's weight.
- Required = the larger of the minimum count and the count needed to reach the WLL.
SOURCE: Rules: 49 CFR 393.100 to 393.136, default WLL table in 393.108 (checked Oct 2026).
Worked example
EXAMPLE
- 24 ft, 12,000 lb, not blocked
- 4 by length
- WLL needed, half of 12,000
- 6,000 lb
- 4 x 4 in straps
- 16,000 lb WLL
Length decides here, not weight. Make the same article 28,000 lb and four 4 in straps give 16,000 lb against 14,000 needed, still fine. At 34,000 lb you'd need five.
Flatbed load securement: what the count misses
- Edge protection. Straps over sharp edges need protectors, or they can't count.
- Condition. Cut, knotted or damaged webbing and stretched chain are out.
- Placement. Tie-downs must be spread along the article and tightened.
- Tarps. Tarps don't count as securement.
- Commodity rules. Machinery, vehicles, coils, lumber and others have their own sections.
Load securement equipment to carry
A typical flatbed or step deck kit: 4 in straps, 3/8 grade 70 chains with binders, edge protectors, a winch bar, dunnage and tarps. A hotshot carries a smaller set sized for its deck and freight. Check every item on your pre-trip and load securement checklist.
Load securement straps vs chains
Straps are light, fast and kind to finished surfaces, but they cut on sharp edges and lose strength when worn. Chains carry more working load per tie-down and suit heavy steel and machinery, but they're heavy and can damage soft cargo. Most flatbed and step deck drivers carry both and choose by the load. Mixing them is fine: add up each tie-down's working load limit to get the total.
Good and bad results
A plan that meets both rules with one spare tie-down is good practice. Exactly the minimum leaves no room if a strap fails inspection at the shipper. Short on either rule: add tie-downs before you roll. Officers check securement at roadside, and a shifted load is a crash risk.
Securement listed before you say yes
Every flatbed, step deck, hotshot and oversize load we bring you comes with the dimensions, weight and securement it needs. You know what to bring before you agree. You approve every load, and the rate confirmation comes straight to you. See rates and fees.
Questions about this calculator
Q01How many tie-downs do I need on a flatbed?
For an article not blocked at the front: one tie-down if it's 5 ft or shorter and 1,100 lb or less, two if it's up to 10 ft, and one more for every extra 10 ft or part of it. The total working load limit must also reach half the cargo weight.
Q02What is working load limit?
The most a tie-down may be loaded in service. Marked straps and chains show it. Unmarked ones get the default value from the federal table, which this tool uses.
Q03Do load securement straps count the same as chains?
They count by working load limit. A 4 in strap at 4,000 lb counts less than a 3/8 grade 70 chain at 6,600 lb. Straps that pass over sharp edges need edge protection.
Q04What cargo securement devices are allowed?
Chains, synthetic webbing, wire rope, cordage, binders, winches, edge protectors, blocking, bracing and friction mats, all meeting the federal rules and in good condition. Damaged devices can't be counted.
Q05Does this cover heavy equipment and cars?
No. Equipment over 10,000 lb, vehicles, coils, logs and some other cargo have their own rules in 49 CFR 393.116 to 393.136. Use those for those loads.