9 Open-Source ChatGPT Alternatives for 2026

Oct 22, 2025 by Ronan McQuillan

Since its launch in 2022, ChatGPT has transformed huge aspects of our daily lives, including in the context of business processes.

However, at a practical level, many organizations still struggle to implement AI tools in a way that drives real value. Part of the issue here is that, while hugely powerful, ChatGPT isn’t always the exact right fit for the needs of large, security-conscious organizations.

Today, we’re exploring one important element of this by checking out the market for open-source ChatGPT alternatives.

Specifically, we’ll be covering:

• What is ChatGPT?
• Why would you want an open-source ChatGPT alternative?
• What to look for in an open-source ChatGPT alternative
• 9 open-source ChatGPT alternatives for 2026

Let’s start with the basics.

What is ChatGPT?

ChatGPT probably doesn’t need much introduction. It’s OpenAI’s flagship AI chat tool. This is not to be confused with the underlying language models that power it, which are currently on the GPT-5 family of LLMs.

It’s built around a conversational interface, which enables users to submit queries and questions via natural language prompts. The model then interprets these before generating responses based on its training data, as well as web-based sources.

Because of this, it has quickly become a ubiquitous part of how users interact with information online, including taking a large slice of usage away from traditional search.

In a professional context, huge numbers of workers also use ChatGPT’s generative capabilities for tasks such as drafting copy, editing emails, writing code, and more. ChatGPT’s more advanced models can even generate images and videos.

Many teams also leverage ChatGPT as part of their workflow automation efforts. This can come in a few different configurations.

One is utilizing Custom GPTs, which are essentially versions of ChatGPT that can be tweaked and customized with specific knowledge, instructions, and capabilities.

Another is utilizing ChatGPT via API connections. This enables us to use ChatGPT within structured workflow automations in a consistent, rules-based manner. For instance, making a call to OpenAI’s API to perform a specific function within a wider workflow.

Recently, OpenAI also introduced ChatKit, which enables teams to build agentic experiences within ChatGPT, including leveraging tool use and embedded UI components within chats.

Alternatively, many AI tools within use-case-specific business platforms are themselves powered by ChatGPT.

For example, ticketing bots within many ITSM platforms.

To support business usage, ChatGPT also offers a range of capabilities for enterprise users, including SSO, data encryption, domain verification, admin tools, and preventing company data from being used in model training.

Why would you want an open-source ChatGPT alternative?

However, as we hinted at earlier, many large organizations have additional requirements that might preclude them from using ChatGPT internally - especially around how they store, process, and control data.

At the same time, IT teams in these kinds of companies are under pressure to provide similar capabilities to their colleagues, often due to widespread usage of ChatGPT outside of IT’s governance and control.

For these kinds of teams, open-source ChatGPT alternatives offer a clear path forward.

One of the key issues here is controlling how and where data is stored.

ChatGPT offers enterprise users the option to prevent their data from being used to train models, but many teams need to go further than this by utilizing open-source models that can be hosted on their own infrastructure.

This is especially important if the chat tool we implement is going to interact with mission-critical data, which already has tight hosting requirements.

Additionally, there are several key operational reasons that we might prioritize an open-source ChatGPT alternative.

One is that these kinds of platforms often offer a high level of configuration, enabling us to closely tailor our solution to our specific requirements in terms of existing workflows.

On top of this, there are commercial factors, such as ongoing cost management and the need to avoid vendor lock-in.

What to look for in an open-source ChatGPT alternative

Understanding why we might prioritize open-source options, we can next move on to thinking about the specific decision points we’re likely to encounter when choosing a specific platform.

Firstly, it’s important to note that these types of solutions don’t always take the form of off-the-shelf, ready-to-use tools in the way that ChatGPT itself or COTS alternatives do.

Instead, we can think about these in two broad clusters:

• Chat and agent frameworks
• Modular chat platforms

However, rather than being a clear distinction, specific platforms often exist on a spectrum between these two clusters.

Therefore, it’s still vital to understand the underlying decision points that could sway us towards one option or another.

Perhaps the biggest thing here is balancing the extent of customization available with how quickly and easily we can output a working solution. For instance, can we build our internal chatbot with visual tools, or will we require extensive development skills?

On top of this, we’ll likely want to consider:

• Security and governance
• Integration depth
• Customization and extensibility
• Ease of implementation
• Scalability and performance
• Community maturity and support
• Operational cost
• Enterprise pricing

Importantly, there’s no one-size-fits-all approach here.

Instead, in order to effectively vet and assess our options, we’ll need to have a clear idea of how each of these factors plays into our own specific requirements, in order to choose the most appropriate open-source ChatGPT alternative for our needs.

9 open-source ChatGPT alternatives for 2026

With a good grasp of why we might opt for an open-source alternative to ChatGPT, some of the specific forms that solutions can take, and the key decisions we’ll need to make when weighing up our options, we can move on to checking out our options on the market today.

In no particular order, these are:

1. Budibase
2. LibreChat
3. LangChain
4. H2oGPT
5. Botpress
6. Jan
7. LM Studio
8. GPT4All
9. Open WebUI

Let’s check each one out in turn.

1. Budibase

Budibase is a complete solution for creating AI-powered workflows, with dedicated Agent, Automation, and App-builders that you can connect to any LLM, data or API, and self-host or use our cloud platform.

Features

Budibase Agents are instruction-led, meaning we can build and iterate over behavior in natural language, including configuring tool calls and data retrieval.

We also offer off-the-shelf chat experiences for Agents, alongside support for existing chat tools. It’s never been easier to create fully custom conversational experiences for all kinds of internal workflows.

Agents can also interact fully with any Data and Automations we grant them access for within our Workspace, making it the perfect solution for invoking agentic workflows from traditional automation rules or building human-in-the-loop controls with Budibase’s leading low-code app-builder.

Use cases

Our users choose Budibase for all kinds of workflows, including internal services, ticketing, approvals, and much more. With fully customizable RBAC, we can tightly tailor permissions to the needs of different roles and colleagues within workflows.

Additionally, Budibase is fully self-hostable and model agnostic, including support for open-source and local LLMs, making it an ideal fit for teams that want to adopt AI in their workflows, without mission-critical data leaving their secure environment.

2. LibreChat

LibreChat offers a huge amount of customization alongside support for a range of LLMs from major providers.

This centers around a pre-built chat UI that will look and feel very familiar to anyone who has used ChatGPT before.

One of LibreChat’s greatest strengths is providing a ready-to-use UI that still offers huge extensibility, including custom presets, a range of configuration options, and support for custom tools and plug-ins.

This makes it a great option for teams that want to build effective internal chat tools without spending extensive time building UIs from scratch.

3. LangChain

LangChain is a developer-focused toolkit, aimed at enabling engineers who need to expedite the process of creating custom tools on top of LLMs.

Part of a wider ecosystem of tools, the LangChain framework itself offers a pre-built agent architecture to enable us to integrate tools and models.

Overall, LangChain is a highly effective option for teams that need to build custom AI-powered solutions, but it’s worth noting that this requires sufficient development skills and resources.

4. H2oGPT

H2oGPT is a comprehensive open-source platform aimed at teams that want to build custom GPTs for offline usage.

The goal is to enable teams to build tools on top of local LLMs, taking advantage of the power of AI, without sacrificing control over their data.

5. Botpress

Billing itself as an all-in-one platform for building AI agents, Botpress provides the core capabilities needed to build production agents.

This centers around a drag-and-drop interface for configuring conversation logic, actions, and integrations.

6. Jan

Jan offers a configurable yet ready-to-use AI chat tool for local and cloud-based models.

It’s available in a range of forms, including a desktop app, a web-based solution, or a self-hosted platform.

7. LM Studio

LM Studio is a platform for running, chatting with, and connecting tools to local models.

8. GPT4All

GPT4All is an open-source application for running AI chatbots with local LLMs.

9. Open WebUI

Open WebUI is perhaps the best-known self-hostable UI for AI chat, making it an important open-source ChatGPT alternative to be aware of.

Turn data into action with Budibase

Budibase is the open-source, low-code platform that empowers IT teams to turn data into action.

With custom Agents, extensive data connectivity, autogenerated UIs, AI-powered automations, custom RBAC, optional self-hosting, and much more.