Chapar

Free plan LinuxMacWindows

What Chapar is

Chapar is a desktop API client for working with REST, gRPC, and GraphQL services. It runs on Linux, macOS, and Windows, and its free, open-source plan costs nothing. Requests support HTTP methods and body types, gRPC reflection or proto files, and GraphQL queries. Python scripts can run before or after a request, with tests in a sandboxed executor. Requests can be grouped into test cases with assertions and captures, then run in CI using chapar-cli.

Workspaces organize requests and collections. Environments store API keys, base URLs, and other service settings, which requests can reference with double-brace syntax. Spaces, requests, and environments are saved as YAML files for review and sharing through git. Chapar says secrets are encrypted with the operating system keychain and that it has zero telemetry. Its public mock API supports REST and gRPC. Imports include OpenAPI specifications, protobuf files, and Postman collections, requests, and environments. Chapar is an early beta project under active development.

Who it suits

Chapar suits developers who want a desktop client for REST, gRPC, and GraphQL work across Linux, macOS, or Windows. Its request chaining, assertions, and CI command are useful for teams that want to run API checks as part of CI.

What it does well

Free and open source, with builds for three desktop operating systems.
Supports REST, gRPC, and GraphQL requests.
Python scripts can run before and after requests.
Test cases can run in CI with chapar-cli.
YAML configuration can be reviewed and shared through git.
Imports OpenAPI, protobuf, and Postman data.

What to know first

Early beta project under active development.
Environment variables are stored as files and may remain on disk when sharing data.
Shared mock API has request-rate, concurrency, and body-size limits.

Limits

The free plan is listed as free. The shared public mock API allows 10 requests per second, bursts up to 30, 10 concurrent requests, and request bodies up to 10 MiB.

Plans

Plan	Billed and limits	Price
Free and open source	Free and open source · macOS, Windows and Linux	Free

As chapar.rest lists them, read 8 Oct 2026. The maker's own page has the final word.

Getting started

Visit https://chapar.rest/.
Choose the desktop build for Linux, macOS, or Windows.
Create a workspace to organize requests and collections.
Import an OpenAPI specification, protobuf file, or Postman collection, request, or environment.
Set up an environment with API-specific values and reference variables in requests.
Chain requests into test cases and run them in CI with chapar-cli.

Verdict

Choose Chapar if you want a free desktop client spanning REST, gRPC, and GraphQL, with scripts and CI-run test cases. Look elsewhere if you need a project beyond early beta or a mock server without the stated shared-service limits.

Questions

How much does Chapar cost?

Its Free and open source plan is free.

Which operating systems does it support?

Chapar is available as a desktop app for Linux, macOS, and Windows.

Which API types does Chapar support?

It supports REST, gRPC, and GraphQL. WebSocket support is listed as unavailable.

Can Chapar run API tests in CI?

Yes. Users can chain requests into test cases with assertions and captures, then run them in CI with chapar-cli.

What can Chapar import?

Supported imports include OpenAPI specifications, protobuf files, and Postman collections, requests, and environments.

Is Chapar open source?

Yes. The site says Chapar is released under the BSD 3-Clause licence.

Facts from Chapar's own pages

Configuration: Spaces, requests and environments are stored as YAML files that users can review and share in git. · chapar.rest, 8 Oct 2026
Encryption and telemetry: The home page says secrets are encrypted with the operating system keychain and Chapar has zero telemetry. · chapar.rest, 8 Oct 2026
Environments: Environments store API keys, base URLs and other API-specific settings, and variables can be used in requests with double-brace syntax. · chapar.rest, 8 Oct 2026
Environment variables: Environments hold API keys, base URLs, and other API-specific settings, and their variables can be referenced in requests with double-brace syntax. · chapar.rest, 8 Oct 2026
Free plan: Yes · chapar.rest, 20 Sept 2026
GraphQL support: Yes · chapar.rest, 20 Sept 2026
gRPC support: Yes · chapar.rest, 20 Sept 2026
Imports: Chapar supports importing Postman collections and environments, OpenAPI specifications, proto files and curl commands. · chapar.rest, 8 Oct 2026
Integrations: The import documentation lists OpenAPI specifications, protobuf files, Postman collections, requests and environments as supported import formats. · chapar.rest, 8 Oct 2026
License: The site footer says Chapar is released under the BSD 3-Clause licence. · chapar.rest, 8 Oct 2026
Local data: The documentation says Chapar stores data locally on the machine and allows changing the data location in settings. · chapar.rest, 8 Oct 2026
Maker: The About page says the project was started by Mohsen Mirzakhani. · chapar.rest, 8 Oct 2026
Mock server: Chapar provides a free public mock API that supports REST and gRPC; GraphQL, WebSocket, and MQTT support are described as planned. · chapar.rest, 8 Oct 2026
Mock server limits: The shared mock server limits clients to 10 requests per second with bursts up to 30, 10 concurrent requests, and 10 MiB request bodies. · chapar.rest, 8 Oct 2026
Organization: Workspaces organize requests and collections. · chapar.rest, 8 Oct 2026
Available platforms: desktop · chapar.rest, 20 Sept 2026
Product: Chapar describes itself as a fast, private, offline API client for REST, gRPC, and GraphQL. · chapar.rest, 8 Oct 2026
Project status: The About page describes Chapar as an early beta project under active development. · chapar.rest, 8 Oct 2026
Purpose: Chapar is an API client for REST, gRPC and GraphQL services. · chapar.rest, 8 Oct 2026
Release status: The home page links to release v0.9.1, and the About page describes Chapar as early beta and under active development. · chapar.rest, 8 Oct 2026
Requests: It supports HTTP methods and body types, gRPC with reflection or proto files, and GraphQL queries. · chapar.rest, 8 Oct 2026
Scripting: It supports Python pre-request and post-request scripts with tests in a sandboxed executor. · chapar.rest, 8 Oct 2026
Scripts: It supports Python pre-request and post-request scripts with tests in a sandboxed executor. · chapar.rest, 8 Oct 2026
Sensitive data limit: The documentation warns that environment variables are stored as files, so sensitive values can remain in the filesystem when sharing data. · chapar.rest, 8 Oct 2026

Where Chapar stands on Freedom251

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