Retool alternative · for Rails teams
Your admin belongs in your Rails app, not another platform.
Leaving Retool? Avo is the Rails admin that lives in your app: your models, your policies, your git workflow, and per-app pricing with unlimited seats.
If your product runs on Rails, your internal tools can live there too. Avo is an admin framework that runs inside your app: it uses the models, validations, and policies you already trust, ships through the git workflow you already use, and adds your whole team for one per-app price.
For Rails teams weighing Retool, or already paying for it and watching the per-seat bill climb as the team grows.
credit where it's due
Retool is a good product, for a different job.
Retool is one of the strongest hosted internal-tool builders out there. It shines when you need to pull many different data sources, several databases, third-party APIs, SaaS tools, into one place and assemble a tool by dragging components around. It doesn't care what your backend is written in, and people who aren't Rails developers can build with it.
If that's the problem in front of you, Retool is a fair choice and the rest of this page won't change your mind. But if your product is a Rails app, a lot of what you pay Retool for is work your codebase has already done.
the core difference
A hosted app builder, or an engine in your repo.
Retool is a platform you build on top of: your tools live in Retool's editor and reach your data through connectors. Avo is a Rails engine you mount inside the app you already have. That one structural choice is where every other difference comes from. It's the same reason every product is really two apps, the one your customers see and the internal one behind it, and why the second one doesn't need to be a separate platform.
Retool
A separate platform
Built in a hosted editor, reaching your database through connectors, priced by the head.
Avo
Inside your Rails app
A mounted engine that reads your models directly, ships in your deploy, and adds no new seat to buy.
It lives in your codebase
Avo runs inside your Rails app, so your data never leaves it. There's no third-party service sitting between your team and your database, and your agents work in the repo they already know.
No black box, no lock-in
When you hit the edge of what's built in, you drop down to plain Rails instead of filing a feature request and waiting on a vendor. You're never stuck with what someone else decided to support.
One mental model
Your whole admin shares Avo's conventions and your app's own code, instead of being a separate UI bolted onto your data. Any Rails developer who knows Avo is productive on day one.
side by side
Avo vs Retool: the same job, measured two ways.
An honest read, Rails team to Rails team. Retool is capable on every row; the question is how much of it you should have to run as a second system.
open source, self-hosted by default
An open-source Retool alternative you already host.
Teams look for a self-hosted Retool for two reasons: the data can't leave their infrastructure, or the bill has outgrown the tool. Retool does offer self-hosting. As of November 2026 it's part of the Enterprise plan: your account executive issues a license key, and your team runs Retool's containers on Kubernetes or Docker in your own cloud, next to the app it serves.
With Avo there is nothing extra to host. Avo Community is free and open source, and it's a gem that runs inside your Rails app. It deploys with your app, reads your database the way your app does, and your data stays where it already lives. Self-hosted is where you start, not a plan you upgrade to.
Retool self-hosted
A second system in your cloud
Enterprise plan, quoted by sales. Your team deploys and upgrades Retool's containers alongside your app.
Avo Community
Part of the app you already run
Free and open source. You add a gem to your Gemfile, and it ships in your next deploy.
Free in every app you build
Community costs nothing in as many apps as you like. Your team gets the CRUD interface, responsive layouts, theming, multi-tenancy, and i18n on day one.
Read the code you run
The source is public on GitHub under the LGPL-3.0 license. When you want to know what the admin does with your data, you open the file.
Paying doesn't move it
Paid features and add-ons install into the same app, priced per app with unlimited users. Your data stays put; what reaches us is a license check on the URL Avo runs on.
Start on Community, and add paid features when your team needs them. The pricing page shows what each plan includes.
it's just Ruby in your repo
This is a working admin for a model.
No editor to log into, no connector to configure. You write a Ruby class, commit it,
and it ships in your next deploy. Here is the entire admin for a User:
# app/avo/resources/user.rb
class Avo::Resources::User < Avo::BaseResource
self.model_class = "User"
def fields
field :id, as: :id
field :name, as: :text
field :email, as: :text
field :admin, as: :boolean
field :projects, as: :has_many
end
end
Add a field, open a pull request, and a teammate reviews the diff before it reaches production, the same review that catches a missing scope or a dropped policy. Your whole team gets the screen, and there's no seat to buy for the next hire. See the full resource DSL in the Avo docs.
when Retool wins
When we'd point you to Retool instead.
We would rather you use the right tool than the one we make. Reach for Retool when:
- Your stack isn't Rails, or you're stitching tools across several different backends.
- The tool needs to sit on top of many heterogeneous data sources at once: multiple databases, third-party SaaS APIs, spreadsheets.
- The people building the internal tools aren't Rails developers, and you want them assembling screens without touching the codebase.
- You want a fully hosted platform where your team maintains none of the plumbing.
If none of those describe you and your product is already a Rails app, the admin doesn't need to be a second platform. Moving an existing internal tool over is its own project, and we've written up how we think about rewriting your admin.
Frequently asked questions
- Is Avo a good Retool alternative for Rails apps?
- Yes, if your product is built on Rails. Avo is an admin framework that runs inside your Rails app instead of on a hosted platform, so your internal tools share the models, validations, and authorization you already wrote. You get the convenience of buying an admin without moving your back office onto someone else's service.
- Retool pricing vs Avo: what does each cost?
- Retool prices per builder and per end user, $10 to $50 per builder per month billed annually as of November 2026, so the bill grows as your team does. Avo 4 is priced per app with unlimited users, so you can add your whole team, and every future hire, without watching the cost scale with headcount. See the Avo pricing page for the current plans.
- Is Retool worth it for a Rails app?
- It depends on what the tool needs to touch. Retool earns its price when one tool spans many data sources, or when the people building it aren't developers. If your product is a Rails app and the admin mostly manages that app's own data, much of what Retool charges for, connecting, authorizing, and rendering UI over your models, is work your codebase has already done, and the per-builder bill keeps growing as you hire. That's the case where an in-app admin like Avo costs less and stays closer to your code.
- Is there an open-source Retool alternative for Rails?
- Yes. Avo Community is free and open source under the LGPL-3.0 license, with the source on GitHub. It's a gem that runs inside your Rails app, so you build your admin on your own models and ship it in your own deploy. Paid plans add features on top, priced per app with unlimited users.
- Can you self-host Retool?
- Yes, on Retool's Enterprise plan, as of November 2026. Free, Team, and Business are cloud only. On Enterprise, your account executive issues a license key and your team runs Retool's containers on Kubernetes or Docker in your own cloud. With Avo there is no second system to run: it lives inside your Rails app, and the free Community edition is self-hosted from the first install.
- Can I self-host Avo?
- Avo isn't hosted anywhere to begin with. It's a Ruby gem that runs inside your own Rails application, so it deploys wherever your app already runs and reads your database the same way your app does. There's no separate service to host, and your data never leaves your infrastructure.
- How is Avo structurally different from Retool?
- Retool is a hosted app builder: your tools live in its editor and reach your data through connectors. Avo is a Rails engine you mount inside your existing app. Because it's part of your codebase, changes ship as code through git and code review, and when you hit an edge you drop to plain Rails instead of filing a feature request.
- Do admin screens built with Avo go through code review?
- Yes. An Avo resource is a Ruby class in your repository, so a change to your admin is an ordinary pull request. A teammate reviews the diff before it reaches production, the same review that catches a missing scope or a dropped policy. Retool offers git-based source control too, but on its Enterprise plan rather than as the default way changes ship.
- When is Retool the better choice than Avo?
- When your stack isn't Rails, when you need to combine many heterogeneous data sources (several databases, third-party SaaS APIs) into one tool, or when the people building the tools aren't developers and you want a fully hosted platform. Retool is a strong product for those situations, and we'd rather you use the right tool for the job.
- Can I move off Avo later without a rewrite?
- Avo is built on tools you already use, ViewComponent, Stimulus, and Hotwire, and it gives you escape hatches to replace parts of it with your own code as you go. Because it's plain Rails underneath, there's no proprietary format to export from and no vendor to migrate away from. You can compare it with other Rails admins on the Avo alternatives page.
→ keep it in your codebase
Your admin belongs in your Rails app.
Start a free trial and mount Avo in your app in an afternoon. Per-app pricing, unlimited seats, and it's your Rails code the whole way down.