TL;DR verdict

Postman is the most feature-complete API platform available — collections, environments, monitors, mock servers, documentation, and team workspaces in one place — but a 2023 policy change requiring cloud sync for all workspace data sparked a significant community backlash. Insomnia responded by going fully open-source under Apache 2.0, dropping its paid cloud tiers, and positioning itself as the privacy-respecting local-first alternative. Postman free tier limits monitors to 25 requests/month; Insomnia is free and open-source with no such restrictions. Choose Postman for the broadest platform capability and team features. Choose Insomnia for open-source transparency, local storage, and a simpler workflow without cloud lock-in.

Quick comparison

FeaturePostmanInsomnia
Starting priceFree planFree plan
Free planYesYes
Open sourceNoYes
Self-hostableNoNo
G2 ratingNot listedNot listed
Best forAPI teams that need a full platform — monitors, mock servers, documentation publishing, and team workspaces — and are comfortable with cloud-first data storage and Postman's pricing modeldevelopers who want a fast, open-source API client that stores everything locally, supports multiple protocols (REST, GraphQL, gRPC, WebSockets), and does not require a cloud account to function
Starting priceFree plan available; Basic at $14/user/month; Professional at $29/user/monthFree and open source (Apache 2.0); no paid tiers for the core client
Free planYes — unlimited API calls, 25 monitor requests/month, 3 mock server calls/month, 1 workspaceYes — fully featured, no usage caps for local use
Open sourceNo — proprietary; collection format is open (Postman Collection v2)Yes — Apache 2.0 license; full source on GitHub (Kong/insomnia, 38k+ stars)
Data storageCloud-required since 2023 — all workspace data syncs to Postman cloud; local-only option removedLocal-first by default — data stays on disk; optional cloud sync available
Protocol supportREST, GraphQL, WebSockets, gRPC (via plugin); SOAP supportedREST, GraphQL, gRPC, WebSockets, Server-Sent Events — all built in natively
MonitorsYes — automated collection scheduling; free tier: 25 calls/monthNo built-in monitors — scripting/automation handled externally
Mock serversYes — full mock server feature with free tier limitsNo native mock server — requires external tools
API documentationYes — auto-generated docs from collections, publishable to public URLNo built-in documentation publishing

Feature breadth and platform completeness

Winner: Postman

Postman is not just an API client — it is a full API development platform. Beyond making HTTP requests, it provides: automated monitors that run collections on a schedule and alert on failures, mock servers that simulate API responses before the backend is built, auto-generated API documentation that can be published to a public URL, and team workspaces with role-based permissions. These features make Postman genuinely useful across the entire API lifecycle — from design and testing to documentation and monitoring. Insomnia is focused on being an excellent API client for making requests and inspecting responses. It does not have monitors, mock servers, or documentation publishing. For teams that need those features, Postman wins outright — Insomnia would require adding separate tools to cover the same workflow.

Privacy, data ownership, and open source

Winner: Insomnia

In 2023, Postman announced that all workspace data — collections, environments, and history — would be required to sync to Postman's cloud servers. The local-only storage option that many teams relied on for security compliance was removed. This change triggered significant backlash from the developer community, particularly from teams handling sensitive API credentials, internal API documentation, or client environments they could not store on a third-party cloud. Insomnia responded directly: it went fully open-source under Apache 2.0, removed its paid cloud tiers, and made local-first storage the default. If you need to keep API collections, authentication tokens, and environments off any third-party server, Insomnia is now the straightforward choice. Postman remains cloud-required for any meaningful use.

Protocol support and request types

Winner: Insomnia

Insomnia natively supports REST, GraphQL, gRPC, WebSockets, and Server-Sent Events without requiring plugins or configuration. gRPC support in Insomnia is particularly well-implemented — proto file importing, streaming call support, and response streaming are all handled cleanly. Postman added gRPC support later and via a more complex setup path. For teams building or testing microservices that use multiple protocols — a REST gateway, gRPC internal services, and a WebSocket notification stream — Insomnia's native multi-protocol support is significantly less friction than Postman's, where some protocols feel like features bolted on after the fact rather than first-class citizens.

Team collaboration and workspaces

Winner: Postman

Postman's workspace and collaboration model is more mature. Team members can share collections, fork and merge them, comment on requests, and assign roles (viewer, editor, admin) at the workspace level. Collection version history, change tracking, and the ability to publish documentation to a team-internal or public URL are all part of the paid plans. Insomnia's collaboration is simpler: file-based sharing or Git sync for teams comfortable with git workflows, with no native commenting or role-based workspace management. For teams where non-developers (QA, technical writers, product managers) need to participate in the API workflow without Git access, Postman's built-in collaboration is meaningfully easier to adopt.

Pricing and cost

Winner: Insomnia

Insomnia is free and open-source with no paid tiers for the core client. There are no usage limits, monitor call caps, or feature gates — you get everything the client offers at $0. Postman's free tier is functional for individual developers but restrictive for team use: 25 monitor requests/month, 3 mock server calls/month, and 1 workspace. The Basic plan at $14/user/month unlocks more workspaces and higher limits; Professional at $29/user/month adds advanced monitors and mock servers at higher volume. For a team of 5, Postman at the Basic tier costs $840/year; Insomnia costs $0. The difference is justified if your team actively uses Postman's monitors, mock servers, and documentation publishing. If you mainly use the tool to make and inspect API calls, Insomnia eliminates the cost entirely.

Performance and user experience

Winner: Insomnia

Insomnia is a native Electron desktop application with a clean, focused interface that prioritizes the request-response workflow. It opens quickly, manages large response payloads without lag, and keeps the UI uncluttered. Postman has grown considerably more complex over the years as it added platform features — the interface now includes flows, environments, monitors, documentation, and workspace management all visible simultaneously. For developers who use the tool primarily to test and debug API calls, Postman's additional UI surface area can feel like overhead. Insomnia's focused scope makes it faster to navigate day-to-day. This is a subjective dimension, but it is consistently cited in user reviews as a reason developers prefer Insomnia for quick, iterative API exploration work.

Pricing deep-dive

Postman

  • Free: unlimited API calls; 25 monitor requests/month; 3 mock server calls/month; 1 workspace; community support
  • Basic: $14/user/month — 5 workspaces per user, 50 monitor requests/month, 5k mock server calls/month
  • Professional: $29/user/month — unlimited workspaces, 10k monitor requests/month, 50k mock server calls/month, advanced integrations
  • Enterprise: custom pricing — SSO, audit logs, static IPs, custom domains

Insomnia

  • Free: $0 — full-featured API client, local storage, no usage limits, open-source Apache 2.0
  • No paid tiers for the core Insomnia client — community-supported and free
  • Kong (the company behind Insomnia) offers paid enterprise API management products separately

Pricing verdict: Insomnia is free, period. Postman starts free but becomes a paid product as soon as you need team workspaces beyond one, meaningful monitor volume, or mock server usage. For teams that need the full Postman platform (monitors, mocks, docs, collaboration), the $14-$29/user/month cost is a fair trade. For teams that mainly need a capable API client without cloud dependency, Insomnia at $0 is straightforwardly better value.

How to migrate from Postman to Insomnia

Data export
Export your Postman collections as Postman Collection v2 JSON files (File > Export in Postman, or via the Postman API). Export your environments as JSON separately. Keep backups — Postman's cloud data is not guaranteed to be available if you close your account.
Import support
Insomnia natively imports Postman Collection v2 format — use Application > Import > From File and select your exported JSON. Environments import as Insomnia Environment files. Test a representative collection after import: request bodies, pre-request scripts, and test scripts use JavaScript in both tools but may need minor syntax adjustments.
Does not migrate
Postman Monitors do not migrate — Insomnia has no equivalent and you would need to set up collection scheduling via CI/CD (Newman, the Postman CLI, or a cron job). Postman Mock Servers do not migrate — alternatives include Prism (open-source), WireMock, or MSW for local mocking. Postman Documentation publishing does not migrate — documentation would need to be hosted separately (Redoc, Swagger UI, or a static site).
Time estimate
Individual developer: 1-2 hours to export, import, and verify collections. Team migration: 1-3 days for collection verification, environment setup, and rebuilding any monitor or mock workflows in external tools. If your team heavily relies on Postman monitors for production API health checks, factor in setting up equivalent monitoring in Datadog, New Relic, or a cron-based Newman runner.

What real users say

Postman: Postman has broad adoption and many teams use it as their default API tool without ever questioning it — the product is deeply embedded in enterprise workflows. The 2023 forced cloud sync change generated some of the strongest negative community response of any developer tools policy change in recent memory, with mass discussion on Reddit and Hacker News and a wave of migration guides to alternatives. Users who stayed generally cite the monitors, mock servers, and team collaboration as irreplaceable. Users who left cite data privacy, the cloud-required policy, and the feeling that Postman's pricing is growing more aggressive as the product matures.

Insomnia: Insomnia gained significant goodwill by going open-source after Postman's cloud-only controversy — it was frequently cited as the recommended migration target in the 2023 backlash threads. Users praise its clean interface, local-first data model, and native gRPC and WebSocket support. The most common complaints are the absence of monitors and mock servers (for teams that need them) and the feeling that active development pace has been uneven since Kong acquired it.

Sources: Synthesized from official pricing pages, vendor announcements, Hacker News threads on the Postman cloud-sync policy change, G2/Capterra reviews, and Reddit developer community discussions.

Final verdict

Choose Postman if...

  • Choose Postman if your team needs the full API platform — automated monitors for production API health checks, mock servers for frontend development against unbuilt backends, and publishable documentation — in one integrated product.
  • Choose Postman if team collaboration with non-technical members (QA, product, technical writers) is important and you need role-based workspace permissions, collection commenting, and shared documentation without Git workflows.
  • Choose Postman if your organization is already on Postman and the switching cost — rebuilding monitors and mocks elsewhere — outweighs the privacy or cost concerns with the cloud-required data model.

Choose Insomnia if...

  • Choose Insomnia if data privacy is a hard requirement and you cannot store API credentials, internal endpoint documentation, or client environments on a third-party cloud — Insomnia stores everything locally by default.
  • Choose Insomnia if you want a free, open-source client with no usage limits and no upsell pressure — it covers REST, GraphQL, gRPC, and WebSockets natively at $0.
  • Choose Insomnia if you are a developer-focused team that primarily uses an API client for request testing and debugging, not for monitors or documentation publishing — Insomnia's focused scope is faster and less cluttered for that core use case.

Consider neither if: Consider Bruno if you want a fully offline, open-source API client where collections are stored as plain-text files in your Git repository (no cloud, no account required). Consider Hoppscotch if you want a web-based, open-source API testing tool that can be self-hosted. Consider HTTPie if you prefer a minimalist terminal-first HTTP client.