Cargo Securement Calculator for Owner Operators

Find the minimum number of tiedowns for your load and check that their working load limit is enough. The math is from 49 CFR 393.106 and 393.110.

The load

Cargo weight

lbs

Article length

The load is blocked from sliding forward by a headerboard, a bulkhead, other cargo that is secured, or another blocking method.

Use the length and weight of one article, or of one group of articles that you secure together.

Your tiedowns

Tiedown set 1

Type, from the 393.108 table

How many

How it is attached

Working load limit used: 2,000 lbs each.

A tiedown is only as strong as its weakest part. Under 49 CFR 393.108, its working load limit is the lowest rating of its parts, including the ratchet, the hooks and the anchor points it is attached to. If a marking differs from the table, use the marking.

This setup meets both rules

Both the count and the working load limit have to pass.

Check 1: how many tiedowns

Minimum tiedowns (393.110)5

Tiedowns you entered10

Enough tiedowns

The article is over 10 feet long, so you need 2 tiedowns plus 1 more for every 10 feet, or fraction of 10 feet, beyond the first 10 feet. That is 3 more (393.110(b)(3)).

Check 2: working load limit

Needed: half the cargo weight (393.106(d))20,000 lbs

Your aggregate working load limit20,000 lbs

Enough working load limit

A tiedown that goes from a vehicle anchor to a cargo anchor counts half. So does one that goes over the cargo and back to the same side. One that goes over the cargo to the other side counts in full.

Quick guide: how many for this load

Tiedown	Over to the other side	Back to the same side
2" strap (2,000 lbs)	10	20
4" strap (4,000 lbs)	5	10
3/8" grade 70 chain (6,600 lbs)	5	7
1/2" grade 70 chain (11,300 lbs)	5	5

Each number meets both rules for this load when you use only that tiedown.

Before you rely on this

These are the general rules. Some cargo has its own rules that come first, such as logs, metal coils, concrete pipe, heavy vehicles and machinery (49 CFR 393.116 to 393.136).
The count rule does not apply to special purpose loads that must be fastened by special methods, but the load must still be secure (393.110(d)).
It does not cover bulk freight that has no fixed shape, such as grain or sand, hauled in a tank, hopper or box.
Check each tiedown for damage before you use it. Our cargo securement rules page covers inspection and the load-specific rules.

Numbers tight? Let a dispatcher find better loads.

This tool is free. If it shows you are leaving money on the road, Grow Trucking finds loads, negotiates rates and does the paperwork for owner-operators and small fleets.

Talk to a dispatcher Call (845) 400-9179

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How many tie-downs does a flatbed load need?

It depends on how long the load is and whether it is blocked from sliding forward. A load that is not blocked needs 2 tie-downs up to 10 feet long, plus one more for every 10 feet, or part of 10 feet, after that. A blocked load needs one for every 10 feet or part of 10 feet. The tie-downs must also add up to a working load limit of at least half the weight of the cargo (49 CFR 393.106 and 393.110).

Count by length (393.110). Not blocked: 1 tie-down for an article of 5 feet or less and 1,100 pounds or less. 2 if it is 5 feet or less and heavier, or if it is over 5 and up to 10 feet. Over 10 feet: 2, plus 1 for every 10 feet or part of 10 feet beyond the first 10. Blocked: 1 for every 10 feet or part of 10 feet.
Add up the working load limit (393.106(d)). The total must be at least half the weight of the cargo. A tie-down that goes from a vehicle anchor to a cargo anchor counts half of its rating. So does one that goes over the cargo and back to the same side. One that goes over the cargo to the other side counts in full.
Example: a 40,000 pound load that is 40 feet long and not blocked needs 5 tie-downs by length and 20,000 pounds of total rating. Ten 2 inch straps rated 2,000 pounds, each going over to the other side, give 20,000 pounds and pass both checks. Six of them give 12,000 pounds and fail.

Minimum tie-downs by length (49 CFR 393.110)
Article length	Not blocked	Blocked
5 ft or less, 1,100 lbs or less	1	1
5 ft or less, over 1,100 lbs	2	1
Over 5 ft, up to 10 ft	2	1
20 ft	3	2
30 ft	4	3
40 ft	5	4

These are the general rules. Cargo such as logs, metal coils, concrete pipe and heavy machinery has its own rules that come first. Use the working load limit marked on the tie-down. If it is not marked, the tables in 393.108 apply. A tie-down is only as strong as its weakest part, including the anchor point. This tool is a check, not a replacement for the rules or for training.

Last reviewed October 2026. Sources: eCFR: 49 CFR 393.106, general requirements for securing cargo; eCFR: 49 CFR 393.108, working load limit of a tiedown; eCFR: 49 CFR 393.110, minimum number of tiedowns.

Frequently Asked Questions - Cargo Securement Calculator

How many tie-downs do I need for a flatbed load?

It depends on the length of the load and whether it is blocked from sliding forward. If it is not blocked, you need 1 tie-down for an article of 5 feet or less and 1,100 pounds or less, 2 for a heavier article of 5 feet or less or one up to 10 feet, and for a longer article 2 plus 1 for every 10 feet, or part of 10 feet, beyond the first 10. If it is blocked by a headerboard, a bulkhead or secured cargo, you need 1 for every 10 feet or part of 10 feet (49 CFR 393.110). The tie-downs must also add up to enough working load limit.

How many tie-downs do I need for a 40 foot load?

An unblocked 40 foot article needs at least 5 tie-downs: 2 for the first 10 feet and 1 for each of the next 30 feet. If it is blocked from sliding forward, it needs at least 4. That is only the count rule. The tie-downs must also have an aggregate working load limit of at least half the cargo weight, and a heavy load can need more tie-downs than the count rule asks for.

How many straps does it take to secure a 42 foot load on a flatbed?

If the load is not blocked, the count rule asks for at least 6 tie-downs: 2 for the first 10 feet, plus 1 more for each 10 feet or part of 10 feet in the other 32 feet. If it is blocked, it asks for 5. Then check the weight. The straps must add up to a working load limit of at least half the cargo weight, counting a strap that goes over the load to the other side in full, and one that returns to the same side at half.

What is the working load limit of a tie-down?

The working load limit, or WLL, is the most force a tie-down can carry in normal use. Under 49 CFR 393.108, the limit of a tie-down is the lowest rating of any of its parts, including the ratchet or tensioner and the anchor points it is attached to. Use the number marked on the tie-down. If it is not marked, the tables in 393.108 give default values, such as 1,750 pounds for 1 3/4 inch webbing, 2,000 for 2 inch, 3,000 for 3 inch and 4,000 for 4 inch.

What is the aggregate working load limit, and how much do I need?

The aggregate working load limit is the total of the credited ratings of all the tie-downs that hold an article or group of articles. It must be at least one-half the weight of the cargo (49 CFR 393.106(d)). For a 40,000 pound load, that is 20,000 pounds. A tie-down from a vehicle anchor to a cargo anchor counts half of its rating. So does one that goes over the cargo and back to the same side. A tie-down that goes over the cargo to the other side counts in full.

Does the number of tie-downs change if the load is blocked?

Yes. If the article is blocked from moving forward by a headerboard, a bulkhead, other cargo that is secured, or another blocking method, the count rule is 1 tie-down for every 10 feet of length, or part of 10 feet. A 30 foot article then needs 3 instead of 4. The working load limit rule stays the same, so a blocked load still needs enough rating.

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