Choose Retool
If you want to build internal tools with ready-made components and database connectors, or write React apps using Retool’s CLI.
Internal-tool platforms
Flex vs Retool
Who do you want building your internal tools?
By the Flex team
Reviewed
Which should you choose?
Choose Flex
If you want your operations team to build the tool themselves, using production data engineering has already approved. They know what the tool needs to do. Engineering decides what it can access.
Retool is not just a drag-and-drop builder. It supports React and coding agents too. Flex also lets your designers work on the product your customers use.
How it works
Starting a project
Retool
Use Retool's current app builder or its CLI to develop Retool-native React applications with a coding agent.
Flex
Start a Hosted App for an internal tool, or connect the repository of the product you want to change.
Connecting data
Retool
Set up database and API connections as Retool resources. Permissions determine who can use them.
Flex
Your engineers connect the database and decide what the app can access. Your team can then build tools using that approved data.
Reviewing changes
Retool
Validate code locally with the CLI. Protected apps can use source control and pull requests.
Flex
Your designer or product manager tries the change in a live preview. Engineering reviews the code before it goes into your product.
Publishing
Retool
CLI publishing enforces function approvals. For a protected app, publishing opens a pull request and waits for merge.
Flex
Share your internal tool through Hosted Apps. For an existing product, use your normal release process.
Flex Hosted Apps Flex configured data access Flex product-change workflow
Maintaining it
Retool
Manage app users, permissions and database connections in Retool. You can use Retool Cloud or run a self-hosted installation.
Flex
Come back to the same app or repository for the next change. Your engineers still review changes to product code and manage access to production data.
Pricing
Retool
Retool charges for builders and app users separately. A tool used by your whole operations team can therefore cost more than one used by two people, even with the same developer. Source control, SSO and advanced permissions also depend on the plan.
Flex
You pay for Flex and the AI you use. With self-hosting, you bring your own model keys and pay for the servers running your previews and apps. Your engineers set up and maintain those servers. Flex hosting takes that server work off your team.
See the linked pricing pages for current prices and plan limits.
Your code and your app
Writing a Retool app locally does not make it independent of Retool: it still uses Retool’s runtime and resource connections. Flex Hosted Apps stores source in Git, but moving an app elsewhere still means setting up its database access and sign-in.
Need an internal tool on production data?
With Hosted Apps, your team builds internal tools using production data engineering has approved. Access controls and governance are built in. You can let Flex host the environment or run it yourself.
Your engineers connect PostgreSQL or ClickHouse, supply the credentials and decide which environment an app can use. Connecting another database or service may need engineering work.
Sources
Official documentation and pricing checked on 27 September 2026. This is our view of the products, based on their documentation rather than a hands-on benchmark.