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Human-in-the-Loop Cost

What does human approval add to each AI workflow run?

How this tool works

This calculator converts approval frequency, approval count, review time, and loaded reviewer cost into human labor per AI workflow run. It also shows monthly review capacity and compares the all-in workflow against the same work completed fully by a person.

Use this when

  • You need to know whether human review erases the savings from an AI workflow.
  • You need reviewer hours or capacity before increasing workflow volume.
  • You are comparing always-review, sampled-review, and exception-only approval patterns.

How It Works

  1. Set monthly workflow volume and comparable AI-assisted and fully human unit costs.
  2. Enter the share of runs reviewed, decisions per reviewed run, review time, and loaded hourly cost.
  3. Compare approval cost, all-in run cost, reviewer capacity, and the approval-rate break-even point.

Formulas

approval_cost_per_run = approval_rate * approvals_per_reviewed_run * review_minutes / 60 * reviewer_cost_per_hour

all_in_cost_per_run = base_ai_and_tool_cost_per_run + approval_cost_per_run

reviewer_hours_per_month = workflow_runs * approval_rate * approvals_per_reviewed_run * review_minutes / 60

Assumptions and Units

  • Currency: USD
  • Approval rate: share of all workflow runs reaching human review
  • Reviewer cost: loaded labor cost per hour
  • Pricing source: explicit user-entered costs; no provider prices are implied

Worked Example

If 25% of runs need one three-minute approval at $65 per reviewer hour, approval labor adds about $0.81 to every workflow run. With $0.25 of AI and tool cost, the all-in run cost is about $1.06.

FAQs

Should approval rate count approvals or runs? Count the share of runs reaching review in approval rate, then use approvals per reviewed run for workflows with multiple gates.

Where does base AI cost come from? Use Agent Run Cost or Tool Use Cost, then enter that result as the pre-review cost.

Related resources: AI Workflow Cost, Agent Run Cost, Tool Use Cost, Break-even Price, Compare Model Costs, Human-in-the-Loop Cost, Agent Run Cost, Tool Use Cost, How Much Does an AI Agent Cost?, How To Price AI Agent Usage With Credits, Caps, and Margin, What Is an AI Agent?.

Pricing source: explicit inputsWorkflow runs: 5,000/moRuns reviewed: 25.0%Review load: 62.5 hrs/mo

Step 1 Workflow Baseline

iSet a comparable AI-assisted and fully human unit before adding approval labor.

Sample review on one-quarter of runs with one short approval decision.

Step 2 Human Review

iApproval probability, decision count, review time, and loaded labor determine the human cost per run.

Scenario actions

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Paste into ChatGPT or Claude, or share with a teammate.

Decision Signal

Below manual

Human approval adds $0.81 per run, bringing the all-in workflow to $1.06 versus a $4.50 fully human baseline.

$17,187.50 lower cost per month at this volume.

Approval labor / run

$0.81

All-in cost / run

$1.06

Reviewer hours / month

62.5

Monthly savings vs. manual

+$17,187.50

Top Cost Drivers

iLargest change in all-in run cost when each input increases by ten percent.
Minutes / approval+$0.08
Runs requiring approval+$0.08
Approvals / reviewed run+$0.08

Cost Comparison

iRun-level and monthly cost after human approval labor is included.
Approval labor / run
$0.81
All-in cost / run
$1.06
Monthly all-in cost
$5,312.50
Monthly fully human baseline
$22,500.00
Monthly savings vs. fully human
+$17,187.50
Approval labor / run$0.81
All-in cost / run$1.06
Monthly all-in cost$5,312.50
Monthly fully human baseline$22,500.00
Monthly savings vs. fully human+$17,187.50

Review Load

iApproval volume, labor, capacity, and the review-rate break-even point.
Labor cost / approval
$3.25
Approval decisions / month
1,250
Reviewer hours / month
62.5
Reviewer capacity required
0.52 reviewers
Approval-rate break-eveniMaximum approval rate at which all-in run cost equals the fully human baseline.
>100%
Labor cost / approval$3.25
Approval decisions / month1,250
Reviewer hours / month62.5
Reviewer capacity required0.52 reviewers
Approval-rate break-eveniMaximum approval rate at which all-in run cost equals the fully human baseline.>100%

Per-Run Breakdown

iThe two cost blocks behind the all-in workflow result.
Base Ai Or Tool CostiModel, tool, and infrastructure cost entered for one run.
$0.25
Human Approval LaboriApproval probability multiplied by approval count, time, and loaded reviewer cost.
$0.81
Base Ai Or Tool CostiModel, tool, and infrastructure cost entered for one run.$0.25
Human Approval LaboriApproval probability multiplied by approval count, time, and loaded reviewer cost.$0.81

Assumptions and Units

iUnits and definitions used by this calculator.
  • CurrencyUSD
  • Workflow unitOne run of the same completed task in both baselines
  • Approval rateShare of all workflow runs reaching human review
  • Reviewer costLoaded hourly labor cost
  • Pricing sourceExplicit user-entered costs; no provider prices are implied

Recommended Next Step

iUse the adjacent calculators to complete the same workflow unit.

Combine this approval layer with agent-run and tool-use cost before setting a price or budget threshold.

Complete the workflow cost

Agent Run CostTool Use CostBreak-even PriceHow To Price AI Agent Usage With Credits, Caps, and Margin

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