Cost Calculation

Sim automatically calculates costs for all workflow executions, providing transparent pricing based on AI model usage and execution charges. Understanding these costs helps you optimize workflows and manage your budget effectively.

How Costs Are Calculated

Every workflow execution includes two cost components:

Base Execution Charge: $0.001 per execution

AI Model Usage: Variable cost based on token consumption

modelCost = (inputTokens × inputPrice + outputTokens × outputPrice) / 1,000,000
totalCost = baseExecutionCharge + modelCost

Model Breakdown in Logs

For workflows using AI blocks, you can view detailed cost information in the logs:

The model breakdown shows:

• Token Usage: Input and output token counts for each model
• Cost Breakdown: Individual costs per model and operation
• Model Distribution: Which models were used and how many times
• Total Cost: Aggregate cost for the entire workflow execution

Pricing Options

Cost Optimization Strategies

• Model Selection: Choose models based on task complexity. Simple tasks can use GPT-4.1-nano while complex reasoning might need o1 or Claude Opus.
• Prompt Engineering: Well-structured, concise prompts reduce token usage without sacrificing quality.
• Local Models: Use Ollama or VLLM for non-critical tasks to eliminate API costs entirely.
• Caching and Reuse: Store frequently used results in variables or files to avoid repeated AI model calls.
• Batch Processing: Process multiple items in a single AI request rather than making individual calls.

Usage Monitoring

Monitor your usage and billing in Settings → Subscription:

• Current Usage: Real-time usage and costs for the current period
• Usage Limits: Plan limits with visual progress indicators
• Billing Details: Projected charges and minimum commitments
• Plan Management: Upgrade options and billing history

Programmatic Usage Tracking

You can query your current usage and limits programmatically using the API:

Endpoint:

GET /api/users/me/usage-limits

Authentication:

• Include your API key in the X-API-Key header

Example Request:

curl -X GET -H "X-API-Key: YOUR_API_KEY" -H "Content-Type: application/json" https://sim.ai/api/users/me/usage-limits

Example Response:

{
  "success": true,
  "rateLimit": {
    "sync": {
      "isLimited": false,
      "requestsPerMinute": 25,
      "maxBurst": 50,
      "remaining": 50,
      "resetAt": "2025-09-08T22:51:55.999Z"
    },
    "async": {
      "isLimited": false,
      "requestsPerMinute": 200,
      "maxBurst": 400,
      "remaining": 400,
      "resetAt": "2025-09-08T22:51:56.155Z"
    },
    "authType": "api"
  },
  "usage": {
    "currentPeriodCost": 12.34,
    "limit": 100,
    "plan": "pro"
  }
}

Rate Limit Fields:

• requestsPerMinute: Sustained rate limit (tokens refill at this rate)
• maxBurst: Maximum tokens you can accumulate (burst capacity)
• remaining: Current tokens available (can be up to maxBurst)

Response Fields:

• currentPeriodCost reflects usage in the current billing period
• limit is derived from individual limits (Free/Pro) or pooled organization limits (Team/Enterprise)
• plan is the highest-priority active plan associated with your user

Plan Limits

Different subscription plans have different usage limits:

Billing Model

Sim uses a base subscription + overage billing model:

How It Works

Pro Plan ($20/month):

• Monthly subscription includes $20 of usage
• Usage under $20 → No additional charges
• Usage over $20 → Pay the overage at month end
• Example: $35 usage = $20 (subscription) + $15 (overage)

Team Plan ($40/seat/month):

• Pooled usage across all team members
• Overage calculated from total team usage
• Organization owner receives one bill

Enterprise Plans:

• Fixed monthly price, no overages
• Custom usage limits per agreement

Threshold Billing

When unbilled overage reaches $50, Sim automatically bills the full unbilled amount.

Example:

• Day 10: $70 overage → Bill $70 immediately
• Day 15: Additional $35 usage ($105 total) → Already billed, no action
• Day 20: Another $50 usage ($155 total, $85 unbilled) → Bill $85 immediately

This spreads large overage charges throughout the month instead of one large bill at period end.

Cost Management Best Practices

1. Monitor Regularly: Check your usage dashboard frequently to avoid surprises
2. Set Budgets: Use plan limits as guardrails for your spending
3. Optimize Workflows: Review high-cost executions and optimize prompts or model selection
4. Use Appropriate Models: Match model complexity to task requirements
5. Batch Similar Tasks: Combine multiple requests when possible to reduce overhead

Next Steps

• Review your current usage in Settings → Subscription
• Learn about Logging to track execution details
• Explore the External API for programmatic cost monitoring
• Check out workflow optimization techniques to reduce costs