Agent Auth & Tool Calling

The 3 Best Nango Alternatives in 2026

Looking for an alternative to Nango? Below we compare the best agent auth & tool calling alternatives by pricing, free tiers, and what each is best for — so you can pick the right fit for your budget and stack.

Category

Agent Auth & Tool Calling

Nango pricing

Free tier available

Free tier

Yes

Alternatives

3 compared

Why look for a Nango alternative?

Nango is a solid agent auth & tool calling choice, but it isn't the right fit for everyone. The most common reasons teams evaluate alternatives:

  • −Elastic License 2.0, not OSI open source
  • −Free self-host excludes syncs, tool calls and MCP
  • −Per-connection pricing grows with users

Nango vs Alternatives — Quick Comparison

ToolPricingFree tierRating
NangoYou searchedFree · paid from $50/mo4.5
1.ComposioFree · paid from $29/mo4.6
2.ArcadeFree · paid from $25/mo4.5
3.ACI.devFree · then usage-based4.1

Top Nango Alternatives, Explained

Composio

1. Composio

Free tier4.6· Free · paid from $29/mo

Composio lets an agent act inside apps such as Gmail, Slack, GitHub, Salesforce and Notion on behalf of each end user. It runs the OAuth flows, stores and refreshes tokens, and exposes each app as ready-made tools for any framework or MCP client, plus triggers that push app events back to the agent. It states SOC 2 Type II and ISO 27001. The SDK is MIT-licensed; the platform is hosted. Pricing changed for signups from August 15, 2026: Hobby is free with 100,000 tool calls and 50,000 trigger events a month (usage pauses at the cap), Pro is $29/month including $29 of usage, then $0.0003 per tool call and $0.003 per trigger event, and Enterprise is custom with SSO, BAA and zero data retention included. Existing customers keep their old plan until December 31, 2026.

  • Largest catalog: 1,500+ apps with managed OAuth
  • Generous free tier (100K tool calls)
  • SOC 2 Type II and ISO 27001
Composio pricing & review Nango vs Composio
Arcade

2. Arcade

Free tier4.5· Free · paid from $25/mo

Arcade.dev runs the tools an agent calls and handles user sign-in for each one, so the agent acts as the authenticated user rather than a shared service account. Every call is limited to what both the user and the agent are allowed to do, and pre- and post-call hooks let you block actions or redact data without forking the runtime. Arcade says its team wrote the MCP tool authorization specification. Custom tools are built with its open-source Python or JavaScript framework (arcade-mcp, MIT). It states SOC 2 compliance, and Enterprise can run in your VPC or fully air-gapped. Free includes 2,000 authorization events and 2,000 tool calls a month; Team is $25/month plus $0.10 per authorization event and $0.01 per tool call; Enterprise is an annual bundle.

  • Per-call authorization scoped to user and agent
  • Policy hooks to block or redact without forking
  • Self-host in your VPC or air-gapped on Enterprise
Arcade pricing & review Nango vs Arcade
ACI.dev

3. ACI.dev

Free tier4.1· Free · then usage-based

ACI.dev (Agent-Computer Interface) is an Apache-2.0 platform that connects agents to 600+ tools through direct function calling or one unified MCP server. It includes multi-tenant OAuth flows and secrets management for each of your end users, dynamic tool discovery, and natural-language permission boundaries on what an agent may do. You can run the full backend and frontend yourself or use the managed service at aci.dev. It is the most permissively licensed option in this category, but the main repository has had no commits since May 2026, so check its activity before you depend on it.

  • Apache-2.0: truly open source and self-hostable
  • Multi-tenant OAuth for end users built in
  • One MCP server for all tools
ACI.dev pricing & review Nango vs ACI.dev
In-depth guideComposio vs Arcade (2026): Agent Auth & Tool Calling, Plus Open-Source Nango and ACI.devYour agent has to act inside Gmail, Slack and Salesforce as each of your users, without the model seeing a token. Composio and Arcade compared with Nango and ACI.dev on OAuth handling, licence and cost at 50 and 1,000 users.

Frequently Asked Questions

What are the best alternatives to Nango in 2026?⌄

The best Nango alternatives in 2026 are Composio, Arcade, ACI.dev. Each is a agent auth & tool calling option you can compare on pricing, free tiers, and features in the table above.

Is there a free alternative to Nango?⌄

Yes — Composio, Arcade, ACI.dev offer free tiers, making them strong free Nango alternatives for bootstrapped startups.

Why look for a Nango alternative?⌄

A common reason teams switch is elastic license 2.0, not osi open source. Beyond that, people compare agent auth & tool calling tools on pricing, specific feature gaps, ease of use, and whether an open-source or free-tier option exists — so they can pick the best fit for their stack and budget.

What is the cheapest Nango alternative?⌄

Composio is among the most affordable Nango alternatives — free · paid from $29/mo. Check the comparison table above for the full pricing breakdown.

Which Nango alternative is rated highest?⌄

Composio is the highest-rated Nango alternative in our catalog at 4.6 out of 5, making it a strong pick if you want a well-reviewed option.

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