The quick answer
Base44 connects to other tools in five ways. Built-in integrations (AI, email, push notifications, file upload, image generation, data extraction) work in every app with no API keys. Connectors are OAuth connections to tools such as Gmail, Slack, Notion, HubSpot or Stripe. Backend functions call any other API with a key stored as a secret. Custom OpenAPI integrations share one API across a workspace, and MCP links your app to AI assistants. Built-in integrations run on any plan; connectors, backend functions, Zapier, payments and MCP need the Builder plan or higher, and integrations spend integration credits, not message credits.
Every rule on this page comes from Base44's integration docs and pricing page, read on 5 November 2026. Each section ends with the guide that covers the build in detail.
Which integration route fits your job
Base44 sorts integrations by where they live: inside one app, across a workspace, or on your account. In practice the question is which job you are doing.
| Your job | Route | Plan | What it costs to run | Guide |
|---|---|---|---|---|
| Add AI answers, send email, upload files, generate images | Built-in integration | Any plan | Integration credits per call | Credits explained |
| Post to Slack, read Gmail, sync HubSpot or Notion | Connector | Builder or higher | Integration credits for the backend function it creates | This page, below |
| Call an API with no connector (Twilio, an internal API, your own OpenAI key) | Backend function + secret | Builder or higher | Integration credits per function run | Connect Base44 to an external API |
| Take payments | Stripe or Base44 Payments | Builder or higher | Integration credits plus the processor's fees | Base44 Stripe guide |
| Trigger tasks in other apps | Zapier, Make or n8n through webhooks | Builder or higher, premium Zapier | Integration credits plus the automation tool's plan | Base44 + Zapier guide |
| Receive events from another service | Webhook into a backend function | Builder or higher | Integration credits per run | Webhooks guide |
| Reuse one API across many apps | Custom OpenAPI integration | Builder or higher to create; any plan to use | Integration credits per call | This page, below |
| Let ChatGPT, Claude or Cursor use your app | App MCP server | Builder or higher | Integration credits | This page, below |
What matters for your Base44 bill is the cost column: every route spends integration credits when it runs. Plans include 100 a month on Free, 2,000 on Starter, 10,000 on Builder, 20,000 on Pro and 50,000 on Elite. Message credits, which you spend while building, are a separate allowance.
Built-in integrations
Built-in integrations are Base44's own managed actions. You do not create accounts or paste API keys; Base44 runs the provider setup and bills the call in integration credits.
- Invoke LLM: AI responses with JSON-schema output, file attachments, image analysis and web search. Every model is available on every plan; a more capable model uses more credits per call.
- SendEmail: email anyone who has signed up to your app, on any plan. Emailing an address that has not signed up needs a paid plan and a verified custom domain. Up to 5 attachments, 5 MB each, 10 MB in total, and no external mailing lists.
- SendPushNotification: native push to one person, for apps with a native mobile build.
- UploadFile and ExtractDataFromUploadedFile: store uploads and pull structured data out of CSV, PNG, JPG, JPEG and PDF files into your tables.
- GenerateImage, plus video, speech and transcription.
- AI Gateway: when the simple calls are not enough, backend functions can call Base44's models directly through common libraries such as the OpenAI SDK and the Vercel AI SDK, still billed in integration credits.
Base44's docs give typical costs as estimates: about 1 credit per email (about 2 from a custom email domain), about 1 per push notification, about 1 credit per 50 characters of speech (up to about 100 per call), about 1 per minute of transcription and about 5 per second of generated video. Credits are calculated after the action runs, and there is no way to preview them, so test an expensive flow on a small sample first. Our cost calculator turns those rates into a monthly figure.
Connectors
Connectors are OAuth connections to your accounts in other tools, and they need the Builder plan or higher. Base44's connectors catalog groups them like this:
- Communication: Discord, Gmail, Google Meet, Microsoft Teams, Outlook, Slack, Zoho Mail.
- Productivity: Asana, Calendly, ClickUp, Google Calendar, Jira, Linear, Miro, Notion, Todoist and more.
- Content: Box, Docusign, Dropbox, the Google Docs, Drive, Sheets and Slides family, Microsoft 365 files, SharePoint, WordPress.com.
- Sales and marketing: Attio, HubSpot, Salesforce, Zoho CRM, Google Search Console, Klaviyo, Mailchimp, Meta Ads.
- Social: Facebook Pages, Instagram Business, LinkedIn, TikTok, X, YouTube.
- Data and finance: Airtable, BigQuery, Databricks, Google Analytics, PostHog, Snowflake, QuickBooks, Square, Stripe.
- Developer tools: Bitbucket, Datadog, GitHub, GitLab, PagerDuty, Sentry.
Two decisions shape every connector:
- Shared or per-user. A shared connector uses one account for everyone, such as alerts to your team's Slack channel. An app user connector lets each person connect their own account, such as each sales rep sending from their own Gmail. Only workspace owners and admins can set up an app user connector, and it runs on your own OAuth client (Google Calendar can use Base44's on the Pro plan and above).
- Base44's OAuth client or yours. With your own client, register
https://connectors.base44.com/api/oauth/callbackas the redirect URI. Connections created before 17 August 2026 use a separate callback URL per app host, so every new app or custom domain needs its URL registered with the provider, or sign-in fails with a redirect-URI error. Base44 lets you switch an older connection to the single URL.
When you use a connector in a flow, Base44 writes a backend function for it. You can read and edit it under Code, in base44 → functions. That matters when something breaks: the connector is only the credential, and the logic lives in that function.
Backend functions and secrets: any other API
For a tool with no connector, your app calls the API from a backend function, with the key stored as a secret in the app's dashboard. This is the route for Twilio-style SMS (Base44 does not send text messages itself), an internal company API, a vendor without a connector, or AI models on your own provider key. It needs the Builder plan or higher.
The working patterns are in three guides: calling an external API or CRM, managing secrets and API keys and receiving webhooks. Code samples should use only SDK names Base44 documents; our SDK reference lists the ones AI agents tend to invent.
Payments: Stripe and Base44 Payments
Charging users needs the Builder plan or higher. You can use Base44 Payments in supported countries, or Stripe. When you set Stripe up from the AI chat, Base44 registers Stripe's webhook and saves the signing secret for you when the payment flow needs one, so you do not create that webhook by hand.
The Base44 Stripe integration guide covers the production setup: customer creation, checkout, webhook processing, reconciling missed events, refunds and testing. When payments that worked yesterday start failing after a platform update, see Stripe integration breaks after an update.
Automation tools: Zapier, Make and n8n
Base44's Zapier integration needs the Builder plan or higher, and Zapier needs a premium account for webhooks. You can start from Base44's ready-made Zapier setup on a new app, or add it to an existing one. Make and n8n work through the same webhook pattern.
Two pages cover it: the Base44 + Zapier production guide and Zapier integration not working.
For automation inside Base44, workflows (Builder or higher) are billed by the steps that run, and a run is cancelled if integration credits run out partway. Failing workflows can keep spending credits on retries, so check the run history.
Workspace and AI-assistant integrations
- Custom OpenAPI integrations: import an OpenAPI spec once and every app in the workspace can call the operations you expose. Only owners and admins on the Builder plan or higher can create or edit one; anyone in the workspace can use it, even on Free.
- App MCP server: a published app can expose its data and actions to AI assistants such as Claude, ChatGPT and Cursor, with access you control. It needs the Builder plan or higher.
- Account MCP connections: separate from your app. They let Base44's AI chat use external tools while you build, without changing the deployed app.
You can mix all of these in one app as long as your plan supports each.
What happens on a downgrade
Base44's docs say built-in integrations stay available on every plan, while connectors, custom OpenAPI integrations, MCP connections and backend-function APIs may stop working until you are back on Builder or higher. Before downgrading, list every flow that depends on a connector or a backend function. A payment webhook or a CRM sync that stops quietly costs more than the plan difference.
When integrations break
The integration problems we see most have their own pages:
- Stripe payments or webhooks fail after a platform update: Stripe integration breaks after an update.
- Zaps do not trigger, or the connection drops after an agent edit: Zapier integration not working.
- Google or Facebook sign-in loops or never establishes a session: Google auth not working and Facebook login fails.
- Users or plans drift between Supabase and Base44: Supabase sync not working.
- Shopify storefront questions: Base44 for ecommerce.
When to bring in help
Most single integrations are a prompt and a test away. Bring in an engineer when the integration carries money or customer data (payments, a CRM sync, per-user OAuth), when it has to survive Base44 regenerating your code, or when you need it across several apps.
We quote integration work at a fixed price before it starts, as part of a Base44 build, and a broken integration is a $1,500 fix sprint that starts within 48 hours of payment and access and is money-back if we cannot resolve it.