Open alternatives8
Open-source apps that replace Retool
ToolJet is a platform for building internal tools such as admin panels, dashboards and operational apps on top of your existing databases and services. It is aimed at teams that need custom work tools, and it can be self-hosted or used as a cloud service.
Appsmith is a platform for building internal business tools such as dashboards and admin panels. It is aimed at teams and organizations that need custom apps for their own staff.

Budibase is an open-source platform for building internal business apps, automations and AI agents without writing much code. It is for teams that want to run their internal tools and workflows on their own servers or on Budibase's cloud.

Windmill is a platform where engineers write small scripts that automatically become web forms, APIs, scheduled jobs, workflows and internal apps. It is aimed at companies that want engineers and business teams to build internal tools together.
ILLA Builder is a tool for developers to quickly build internal business tools, such as admin panels and dashboards, by dragging ready-made components onto a canvas and connecting them to databases or APIs. It is aimed at programmers and teams who need custom internal software.

Openblocks is a tool for building internal business apps, such as dashboards and admin panels, by connecting to databases and APIs and arranging ready-made components on screen. It is aimed at software teams and companies that need custom tools for their staff or customers.

Lowdefy is a framework where you describe a web app in YAML config files instead of writing code, and it runs the app for you. It is aimed at developers and teams who build internal business tools.
DashPress turns a database into a ready-made admin dashboard for managing its records. It is aimed at developers and teams who need an internal admin panel without writing much code.
What's missing
What people still miss here, and wish existed. Upvote what matters to you.
Before you build
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Fix the list itself
A project or closed app missing from this list, or a mistake on it? These open a short form on GitHub, and a mod reviews it. To say what a project can't do, use What's missing.
About this page
Replaces fully means it does the main job of these apps; Replaces partly means it covers some of it.
Licenses: every project here uses an open-source license (what each one means). Open core means some parts are paid or under another license.
GitHub stars are shown for reference. They measure popularity, not whether it replaces anything.
Verified means r/TrueOpenSource mods checked it: open-source license, maintained, and it really does the job.
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