Best ChatGPT Enterprise Alternative (2026) | Onyx vs ChatGPT Enterprise

The open-source ChatGPT Enterprise alternative

Onyx searches across 40+ tools, respects permissions out of the box, and runs anywhere. No model lock-in, no cloud-only limitations.

Feature Onyx ChatGPT
Flexible deployment Cloud, hosted in your cloud, or fully on-prem Cloud only
Integrated company knowledge +33 more
40+ indexed enterprise connectors
~10 indexed, rest MCP
1
Model-agnostic (100+ LLMs) Yes No
Advanced agent creation Attach any connected knowledge, MCP + OpenAPI actions OpenAPI actions only
Deep research Yes Yes
Projects Yes Yes
Image generation Any model (Nanobanana, GPT Image, more) OpenAI models only
Open-source Yes No

1MCP connectors fetch data live at query time: slow, incomplete, and limited to what a single API call returns. Indexed connectors continuously sync your data in the background, enabling instant, comprehensive, permission-aware answers.

More Accurate Answers

Independent evaluation across 99 real-world workplace questions using 220K internal documents from Slack, Google Drive, GitHub, Gmail, and more.

Overall Win Rate

Fact Lookup

Based on 99 real-world workplace questions across 220K internal documents. Judged by GPT-5.2 and Claude Opus 4.5. Read the full benchmark

Pricing Comparison

Try the Business edition on our Cloud ($20/user/month). 14-day free trial. No credit card required.

Enterprise edition adds SLAs, dedicated support, and white-labeling.

~150-seat minimum for Enterprise. Credits-based billing for advanced features. Annual commitment required.

Total Cost of Ownership

Estimated annual cost comparison based on per-user pricing.

Team size Onyx ChatGPT
100 users $24,000 $72,000
10 $20/user/month ~$60/user/month
1,000

Annual Savings

$48,000
67% less with Onyx.

Detailed Comparison

Click each section to expand the full comparison.

Enterprise Search & Connectors

Onyx was built from day one as an enterprise search platform. 40+ native connectors continuously crawl and index your data from Slack, Google Drive, Confluence, Jira, GitHub, Salesforce, and more. Permission syncing ensures users only see what they have access to in the source system. Hybrid search combines semantic and keyword retrieval for best-in-class answer quality.

ChatGPT Enterprise

ChatGPT Enterprise launched "Company Knowledge" in October 2025. It supports ~10 synced (indexed) apps and additional on-demand apps including Google Drive, SharePoint, Slack, Notion, and GitHub. Synced apps pre-index content while other apps query on-demand. Permission-aware retrieval is available but inherits oversharing risks from source systems; if your Google Drive permissions are too broad, ChatGPT will surface that data to anyone.

AI Model Flexibility

Deployment & Data Sovereignty

Custom Agents & Actions

Security & Compliance

Which is Right for You?

Onyx is best for

ChatGPT Enterprise is best for

When we work in a sensitive defense space, we prioritize suppliers that are big, established companies with a lot of reputation at stake, or services that we can self-deploy so that we control where the data goes.

Frequently Asked Questions

Get Started

Start your 14-day free trial of Onyx (no credit card required).

Secure enterprise-grade security and compliance. Flexible and secure deployment options.

Open-Source deep customizability optimized for your use case, supported by a large Open-Source community.