Why add the stop instead of a percentage allowance?

Because a stop freezes the whole queue for its full length. Every queued unit waits that many extra minutes, so a 5-minute jam adds 5 minutes whatever the queue size; a percentage would wrongly scale with the queue.

Which consumption rate should I enter?

Enter the next station's rate while running, from its counter over a few clean hours or 60 ÷ its cycle time in seconds. Put its stops in the stop field so they are not counted twice.

Does Little's law apply to a conveyor queue?

Yes. Little's law says average units in a system equal throughput times average time in it, and it holds for a queue inside a line. Units in queue ÷ consumption rate is that law rearranged.

What if my product has no time limit?

Enter the longest wait you will accept, such as a first-in, first-out window from your quality plan. The two queue time rows do not depend on the limit, so they hold either way.

Conveyors calculator

Conveyor Queue Time Calculator

Find how long the last unit on an accumulation conveyor waits for the next station, including a downstream stop. You need a queue count, the downstream running rate and your time limit.

What this calculator does

How long the last part in a conveyor queue waits for the next station, and whether that fits your product's time limit.

Formula used

Queue time at steady flow = units in queue ÷ downstream consumption rate
Longest queue time = queue time at steady flow + downstream stop
Margin to limit = queue time limit − longest queue time
Largest queue within the limit = (queue time limit − downstream stop) × consumption rate, rounded down
Consumption rate needed = units in queue ÷ (queue time limit − downstream stop)

Inputs explained

Units in Queue: Units counted on the accumulation conveyor ahead of the next station.
Downstream Consumption Rate: Units per minute the next station takes while running, from its counter.
Downstream Stop to Plan For: A stop length from your downtime log; 0 for steady flow.
Queue Time Limit: Longest wait the product allows, such as adhesive open time.

How to use the result

Best suited to keeping bonded parts inside adhesive open time, checking a buffer after a downstream jam, setting a maximum queue on an accumulation conveyor.
Units arriving behind the counted queue wait longer if upstream outruns the next station; recount at the peak. Does not model several stops during one wait, or slow running between stops.

Current U.S. benchmarks

The U.S. has 21,668 machinery manufacturing establishments employing about 1,086,146 workers (Census County Business Patterns, 2023).

Common questions

Why add the stop instead of a percentage allowance? Because a stop freezes the whole queue for its full length. Every queued unit waits that many extra minutes, so a 5-minute jam adds 5 minutes whatever the queue size; a percentage would wrongly scale with the queue.
Which consumption rate should I enter? Enter the next station's rate while running, from its counter over a few clean hours or 60 ÷ its cycle time in seconds. Put its stops in the stop field so they are not counted twice.
Does Little's law apply to a conveyor queue? Yes. Little's law says average units in a system equal throughput times average time in it, and it holds for a queue inside a line. Units in queue ÷ consumption rate is that law rearranged.
What if my product has no time limit? Enter the longest wait you will accept, such as a first-in, first-out window from your quality plan. The two queue time rows do not depend on the limit, so they hold either way.

Last reviewed 2026-10-01.