Looker Studio ships with native connectors for Google’s own products but nearly every analytics stack includes third-party tools: CRMs, email platforms, call tracking software, data warehouses from other vendors. For these you either find a community connector from the gallery or build your own. This guide explains how to evaluate community connectors, when they are not trustworthy, and how to build your own when none of the existing options are adequate.

The Community Connector Ecosystem

Looker Studio’s connector gallery contains hundreds of community-built connectors for platforms like HubSpot, Salesforce, Mailchimp, Ahrefs, Stripe, and dozens of others. These connectors are built and maintained by third parties — Google does not vet their quality, accuracy, or security practices. When you connect a third-party connector, you are authorising that connector’s code to access your data on the platforms it connects to. Always verify the connector’s author and review their privacy policy before connecting any source that contains customer data or PII.

Evaluating Connector Quality

Look for: how many users have connected (displayed in the gallery), average rating and volume of reviews, date of the most recent update, and whether the documentation matches what you need. Connectors not updated in over a year may be incompatible with API changes. Connectors with fewer than 100 users have not been broadly tested. Connectors rated below 3 stars with more than 20 reviews have documented problems — read negative reviews to understand whether issues are fundamental data accuracy problems (avoid) or minor usability complaints (acceptable).

When to Build Your Own Connector

Build your own when: no existing connector covers the API you need, existing connectors are unreliable or outdated, or you need to connect an internal database or custom API. Looker Studio’s connector framework supports any HTTP-accessible data source through Apps Script, which is free and already accessible through your Google account.

Building a Connector with Apps Script

A Looker Studio connector built with Apps Script has four required functions: getAuthType() defines the authentication method, getConfig(request) defines the configuration form users fill in when setting up the connector, getSchema(request) defines the fields available in the connector, and getData(request) fetches and returns the actual data. The getData() function is called every time a chart refreshes, so implement caching using Apps Script’s CacheService to avoid exhausting API rate limits and to keep report loading fast.

Caching in Custom Connectors

function getCachedData(url, cacheKey, cacheDuration) {
  var cache = CacheService.getScriptCache();
  var cached = cache.get(cacheKey);
  if (cached) return JSON.parse(cached);
  var response = UrlFetchApp.fetch(url);
  var data = response.getContentText();
  cache.put(cacheKey, data, cacheDuration);
  return JSON.parse(data);
}

Deploying and Sharing Custom Connectors

Custom connectors can be deployed as private (only you), domain-wide (everyone in your Google Workspace), or public (submittable to the gallery). For internal business use, private or domain-wide deployment is appropriate and avoids the review process required for public gallery submission. To share a private connector: deploy as a web app in Apps Script, copy the deployment ID, and share it with colleagues who will add it to Looker Studio by entering the deployment ID in the Custom connector section of the data source picker.