Powering Simulations with Real-Time Data

The problem with static assumptions

Traditional simulation tools treat inputs as one-time entries. You gather your data, type it in, run your model, and move on. But real-world assumptions don't work that way.

• Market data changes constantly — Stock prices, exchange rates, and commodities shift by the minute
• Business metrics evolve — User growth, churn, and conversion rates are living numbers
• Teams maintain data separately — Finance owns the spreadsheet, product owns the analytics

Every copy-paste introduces friction. And friction means your models drift from reality.

Introducing Connections

Connections are live data sources that feed directly into your simulations. Create a connection once, and every referenced value stays in sync with the source.

The syntax is simple: @connection_name.field_name

// Reference live data in any formula
base_revenue * @assumptions.growth_rate

// Combine multiple sources
@sales.revenue * shares * (1 + @analytics.user_growth)

Seven ways to connect

We've built integrations for the most common data sources. Each one takes minutes to set up and works seamlessly with Carlo's formula engine.

Manual

Enter values directly for quick assumptions and scenario testing.

@assumptions.growth_rate

Webhook

Receive updates from Zapier, Make, or any automation tool.

@crm.pipeline_value

PostHog

Pull analytics metrics: events, users, pageviews, custom queries.

@analytics.unique_users_7d

Stripe

Sync billing metrics: MRR, ARR, customer counts, and revenue.

@billing.mrr

Airtable

Pull data from Airtable bases and tables with name/value pairs.

@metrics.conversion_rate

Notion

Sync from Notion databases. Great for team-managed assumptions.

@notion_data.growth_rate

REST API

Connect any JSON endpoint. Use for custom APIs and internal tools.

@api.active_users

How it works

Setting up a connection takes three steps:

1. Create the connection — Choose a type and give it a name like market or analytics
2. Configure the source — Enter credentials, select data, or set up the webhook
3. Reference in formulas — Use @connection.field anywhere you'd use a number

Use cases

Here's what you can build with connections:

SaaS forecasting with real metrics

Connect PostHog to feed your user count, event volumes, and conversion rates directly into revenue projections. As your product grows, your forecasts update automatically.

Team-maintained assumptions

Finance updates growth assumptions in Notion or Airtable. Product updates conversion rates. Your simulation pulls from both, always in sync, no meetings required.

Revenue forecasting with Stripe

Connect Stripe to pull your actual MRR, ARR, and customer counts into projections. As your revenue grows, your forecasts stay accurate without manual updates.

Automated data pipelines

Use webhooks to push data from Zapier, Salesforce, or your CRM. When pipeline value changes, your projections update instantly.

Custom API integrations

Connect any JSON API with the REST API connection. Pull data from internal dashboards, custom analytics systems, or any service that returns JSON.

Getting started

Connections are available now for all Carlo users:

1. Open any simulation you own
2. Click the settings icon and navigate to Connections
3. Add a connection and choose your data source
4. Use @connection.field in any formula

Check out the Connections documentation for detailed setup guides and examples.

We're excited to see what you build. Tag us with your connected simulations—we'd love to feature the most creative uses.