Comparison of API simulation tools

The tools listed here support emulating^[1] or simulating APIs and software systems. They are also called^[2] API mocking tools, service virtualization tools, over the wire test doubles and tools for stubbing and mocking HTTP(S) and other protocols.^[1] They enable component testing in isolation.^[3]

In alphabetical order by name (click on a column heading to sort by that column):

Name	FOSS	Free	Supported protocols and APIs	Has a GUI	Scriptable/Programmable	Docker support	Cloud offering
API Simulator	No; Proprietary[4]	Yes	HTTP/2 with TLS ALPN; HTTP/2 with prior knowledge; HTTP/2 upgrade from HTTP/1.1; HTTP/1.x with and without TLS/SSL; HTTP(S)	Yes[5]	Yes[6][7]	Yes[8]	No
apiUi	Yes; GPL v3.0[9]	Yes	HTTP(S); STOMP, WSDL; Swagger; OpenAPI; Cobol	Yes[10]	Yes[11]	Yes[12]	No
Beeceptor	No; Proprietary[13]	Yes (Free plan)	HTTP1.1; HTTP2; HTTP(S); SOAP, MITM/Proxing; Swagger; OpenAPI; TLS 1.2; XML; Local tunneling	Yes	Yes[14]	Yes	Yes
Camouflage	Yes; MIT[15]	Yes	HTTP(S), HTTP/2 gRPC, Websockets, Thrift	Yes[16]	Yes[17]	Yes[18]	No
Charles Proxy	No; Proprietary[19]	No	HTTP(S)	Yes	No	No	No
Ekko Proxy	No; Proprietary	Yes (non commercial use)[20]	HTTP(S), JDBC; WSDL, Swagger, OpenApi, JWT.	Yes[21]	Yes (Scriptable)	Yes	No
HAM	Yes; MIT	Yes	HTTP(S), SOAP, MITM/Proxing, Swagger, XML, JSON, Jackson-Smile, Brotli, Record, Replay, Automatic tests, Schema verification, JDBC, MongoDb	Yes (Web)	Yes (Dynamic Javascript and Java Plugins)	Yes	No
Hoverfly	Yes; Apache 2[22]	Yes	HTTP(S)	Yes	Yes	Yes	Yes [23]
HTTP Toolkit	Yes; AGPL[24]	Yes (Hobbyist Edition)[25]	HTTP(S)	Yes	No	No	No
Int4 IFTT	No; Proprietary	No	HTTP(S), Middleware virtualization: SAP Process Orchestration, SAP Intelligent Suite, Dell Boomi, Software AG Webmethods, SAP IDOCs	Yes	Yes	No	No
Karate	Yes; MIT[26]	Yes	HTTP(S), Java interop[27]	No	Yes[27]	No	No
Keploy	Yes	Yes	HTTP(S), OpenAPI, gRPC	Yes	Yes	Yes	Yes
LogDog	No; Proprietary[28]	No	HTTP(S), HTML, XML, JSON, Replay, Real-Time-Monitoring, 1-Click-Mocks	Yes	Yes	No	Yes
Microcks	Yes; Apache 2[29]	Yes	HTTP(S), SOAP, gRPC, GraphQL, AsyncAPI[30]	Yes	Yes	Yes	No
Mockadillo	No; Proprietary	No	HTTP(S)[31]	Yes	Yes	No	Yes
Mocklets	No; Proprietary[32]	Yes	HTTP(S)	Yes	No	No	Yes [33]
Mockoon	Yes; MIT[34]	Yes	HTTP(S)[35]	Yes	Yes	Yes [36]	No
MockServer	Yes; Apache 2[37]	Yes	HTTP(S)	Yes[38]	Yes	Yes	No
mock.qa	No; Proprietary	Yes (Free plan)[39]	gRPC, gRPC-web, HTTP/1.x, HTTP/2[40]	Yes[41] (Web)	Yes[42][43] (Scripting language,[44] Request matching,[45] Response templating,[46] Data generation,[47] Stateful scenarios[48])	No	Yes
Mountebank	Yes; MIT[49]	Yes	HTTP(S), TCP, SMTP[50]	No	Yes[51]	Yes[52]	No
NetOcean	No; Proprietary	No	Web Services Protocols: HTTP, HTTPS, HTTP2, REST, SOAP, Hessian Others: IMAP, FTP, DNS, XML, JSON, WebSocket ESB / Middleware Protocols, TIBCO JMS Database Protocols: JDBC Proprietary: TCP, UDP Platforms: TIBCO-EMS, IBM-MQ, Kafka SOA Protocols: SOAP, HTTP, XML, REST SMS Gateway Providers: SMTP, POP3 Bill Payments Services: Gift card- PINPAD, AJB	Yes	Yes	Yes	Yes
Parasoft Virtualize	No; Proprietary	Yes (Community Edition)[53]	AMQP, FIX, FTP, HTTP(S), ISO 8583, JMS, JDBC, MQ, MQTT, .NET WCF, RabbitMQ, SAP, TCP/IP, etc.[54]	Yes	Yes	Yes[55]	Yes
Postman	No; Proprietary	Yes (Free Edition)[56]	HTTP(S)	Yes	Yes (JSON Examples)	No	Yes
ProxyMan	No; Proprietary	Yes,[57] (Limited)	HTTP(S), Websockets	Yes	Yes[58]	No	No
QuickMocker	No; Proprietary	Yes (Free Subscription)[59]	HTTP(S)	Yes	Yes[60]	No	Yes
Rapidmock	No; Proprietary[61]	Yes (Free Edition)	HTTP(S)	Yes	No	No	Yes
Requestly	Yes; GPL v3.0[62]	Yes[63]	HTTP(S)	Yes	Yes	No	Yes[64]
sMockin	Yes; Apache 2[65]	Yes	HTTP, Websockets, Server Side Events, plus tools for real time monitoring & live response modification	Yes	Yes	Yes	No
Smocker	Yes; MIT[66]	Yes	HTTP(S)[67]	Yes	Yes	Yes	No
SmartMock.io	No; Proprietary[68]	Yes [69]	HTTP(S)	Yes	Yes	No	Yes
Specmatic	Yes; MIT[70]	Yes (Basic Plan) [71]	HTTP(S), Swagger, OpenAPI, WSDL, Kafka, AsyncAPI, GraphQL, gRPC, Arazzo, Protobuf, JDBC, Redis, JMS, Google Pub/Sub [72]	Yes [73]	Yes	Yes	Yes
simulado	Yes; MIT[74]	Yes	HTTP(S)	No	Yes	Yes	Yes
SoapUI MockServer	Yes; EUPL[75]	Yes	HTTP(S)[76]	Yes[76]	No[76]	No[76]	No[76]
Speedscale	No; Proprietary	Yes, (Free Trial)[77]	HTTP(S), gRPC, GraphQL webservices, Message queues, OSS Databases[78]	Yes	No, Not required. Traffic recording-based[79]	Yes	Yes
Stoplight	Yes; Apache 2[80]	Yes (Free Edition)[81]	HTTP(S) and generate mocks directly from OpenAPI	Yes	Yes	Yes	Yes
TPM-Proxy	Yes; MIT	Yes	Direct Wire Protocol implementation: HTTP(S), SOAP, MITM/Proxing, OpenAPI, XML, JSON, Jackson-Smile, Brotli, MongoDb, Postgres, MySQL, AMQP 091, MQTT, REDIS, Record, Replay, Modify	Yes	Yes (Java Plugins)	Yes	No
tweak	No; Proprietary	Yes	HTTP(S)	Yes	No	No	No
Tricentis API Simulation	No; Proprietary	Yes(Free Edition)[82]	Http(s), AmazonSqs, AMQP, AzureServiceBus, Files, IbmMQ, Kafka, RabbitMQ, Solace	Yes [82]	Yes [82]	Yes [83]	Yes [82]
Wilma	Yes; GPL v3.0[84]	Yes [85]	HTTP(S)	Yes	Yes	Yes [86]	No
WireMock	Yes; Apache 2[87]	Yes	HTTP(S), gRPC, GraphQL	Yes	Yes	Yes	Yes [88]
WireMock.Net	Yes; Apache 2[89]	Yes	HTTP(S)	No	Yes	Yes [90][91]	No
Wiresham	Yes; Apache 2[92]	Yes	TCP	No	Yes	No	No

See also

• Test double
• Service virtualization

References

1. Thought Works Technology Radar Mountebank
2. Tom Akehurst at the Next Gen Service Virtualisation Forum
3. Martin Fowler, Microservce Testing, Component Testing
4. API Simulator License Agreement
5. API Simulation Modeler
6. Scripting in API Simulator
7. Simula Template Scriptlets
8. API Simulator in Docker Container
9. apiUi License
10. The apiUi GUI
11. apiUi Scripting; adding dynamics
12. apiUi Docker
13. Beeceptor pricing
14. Handlebar templates for scripting; adding dynamic responses
15. Camouflage License
16. Camouflage UI
17. Scripting in Camouflage
18. Camouflage Docker
19. Charles Proxy EULA
20. Ekko Proxy License Agreement
21. Ekko Proxy Usage
22. Hoverfly license
23. Hoverfly Cloud
24. HTTP Toolkit license
25. HTTP Toolkit tiers
26. Karate license
27. Karate-Netty home page
28. LogDog
29. Microcks License
30. Using Microcks
31. "Mockadillo". Mockadillo Homepage.
32. Mocklets Terms of Use
33. Mocklets
34. Mockoon license
35. "Mockoon". Mockoon features page.
36. Mockoon CLI dockerhub
37. MockServer License
38. MockServer Dashboard
39. Mock.qa: Free plan on GitHub Markeplace
40. Mock.qa: Supported protocols
41. Mock.qa: Playground
42. Mock.qa: Configuration
43. Mock.qa: Configuration examples
44. Mock.qa: Scripting language
45. Mock.qa: Request matching
46. Mock.qa: Response templating
47. Mock.qa: Data generation
48. Mock.qa: Stateful scenarios
49. Mountebank license
50. Moutebank home page
51. Mountebank injection
52. Running Mountebank in Docker
53. Parasoft Virtualize Community Edition
54. Parasoft Virtualize home page
55. Virtualize Docker Files 1.0
56. Postman Pricing
57. Proxyman Pricing
58. Proxyman scripting
59. QuickMocker Pricing
60. QuickMocker RegExp & Shortcodes
61. Rapidmock home page
62. "requestly/requestly". GitHub.
63. Requestly Pricing
64. Requestly Clound Based Mock Server
65. "Matthewgallina/Smockin". GitHub. 27 March 2022.
66. Smocker License
67. Smocker documentation
68. SmartMock.io Terms of Use
69. SmartMock.io pricing
70. "Specmatic". GitHub.
71. "Pricing - Specmatic".
72. [1]
73. Specmatic Studio
74. simulado license
75. SoapUI Licence
76. SoapUI MockServer documentation
77. "Speedscale Free Trial Version". Speedscale. Retrieved 2024-03-20.
78. "Technology Support | Speedscale Docs". docs.speedscale.com. Retrieved 2024-03-20.
79. "How Traffic Recording Works". Speedscale. Retrieved 2024-03-20.
80. Prism Licence
81. Stoplight Pricing
82. "Discover Tricentis Tosca in the cloud".
83. "Simulate services".
84. Wilma License
85. Wilma Feature list
86. Docker images of Wilma
87. WireMock License
88. WireMock Cloud
89. WireMock.Net License
90. WireMock.Net .Net Core 2.0 Linux image
91. WireMock.Net .Net Core 2.0 windows-nano image
92. Wiresham License