Problem

Requestly addresses a recurring software-development bottleneck: frontend and QA teams cannot reliably develop or test against APIs that are unfinished, unstable, difficult to access, or controlled by another team. Waiting for backend releases, coping with flaky staging environments, and negotiating API contracts can delay releases, block sprints, and force developers to switch between separate debugging and API-testing tools. The resulting pain is primarily wasted engineering time and slower feedback during development.

Its clearest use case is a frontend team building before the backend is ready. Requestly lets developers intercept the application's API calls and return realistic mock responses without changing backend code, then simulate difficult states such as missing fields, 400 or 500 errors, and timeouts. This allows teams to validate UI behavior and error handling immediately rather than waiting for backend work or constructing elaborate test environments.

Product / Service

Requestly combines a local-first API client with an HTTP-interception toolkit. Its browser extension and desktop applications for macOS, Windows, and Linux can intercept traffic and redirect URLs, change request or response headers, inject JavaScript or CSS, block or delay requests, and override REST, GraphQL, and other API responses. The API client adds collections, environments, scripting, GraphQL testing, and API test execution, so developers can design and test an API in the same workflow where they debug and modify live traffic.

The product is delivered through a free local workflow and paid collaboration and governance tiers. Users can keep data in local files or Git, while team features provide shared projects, synchronization, collaboration, and enterprise controls; the company also describes self-hosted deployment for organizations requiring data sovereignty. The core benefit is faster, safer feedback without modifying production or backend systems, with less context switching and less dependence on cloud-hosted data.

Market

Requestly competes across API mocking, API development and testing, API-client, and HTTP-interception or network-debugging categories. Its most direct named comparators are Postman, which is the principal API-client alternative, and Charles Proxy, whose traffic-interception functionality Requestly combines with Postman-like API testing. G2 places Requestly primarily in API Mocking Software while also associating it with API Platforms and iPaaS, reflecting a product that sits between developer debugging, frontend testing, and the broader API lifecycle.

The company has meaningful commercial and distribution traction rather than presenting as a pre-revenue project. Requestly's pricing page claims more than 50,000 companies and more than half of Fortune 500 companies use it, while its Chrome listing claims more than 300,000 developers; its free tier is complemented by a paid Pro subscription priced at $12 per user per month, or $9 annually. BrowserStack announced its acquisition of Requestly on May 6, 2025, and the extension now identifies Requestly as part of BrowserStack. The evidence establishes substantial adoption and a paid product model, although it does not provide independently verified revenue figures.