Comparison of API simulation tools


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

In alphabetical order by name :


NameFOSSFreeSupported protocols and APIsHas a GUIScriptable/ProgrammableDocker supportCloud offeringQuick start guide
API Simulator; ProprietaryHTTP/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
Charles Proxy; ProprietaryHTTP
; Proprietary HTTP, plus various tools to securely compare, encode/decode, format, match, and hash data, validate / encode JWT tokens.
Hoverfly; Apache 2HTTP
; AGPL HTTP
Karate; MITHTTP, Java interop
Mockadillo; ProprietaryHTTP-
; ProprietaryHTTP
MockServer; Apache 2HTTP
Mountebank; MITHTTP, TCP, SMTP
Parasoft Virtualize; Proprietary AMQP, FIX, FTP, HTTP, ISO 8583, JMS,
JDBC, MQ, MQTT,.NET WCF, RabbitMQ, SAP, TCP/IP, etc.
sMockin; Apache 2HTTP, Websockets, Server Side Events, JMS, FTP
simulado; MITHTTP
SoapUI MockServer; EUPLHTTP
Traffic Parrot; ProprietaryHTTP, JMS, IBM® MQ, File transfers, gRPC, Amazon Simple Queue Service, Azure AMQP Service Bus

In beta: FIX, FAST, FIXatdl, SWIFT, AMQP, MQTT, RabbitMQ, SonicMQ, Kafka,
CORBA, FTP, SFTP,.NET WCF, RMI, MTP,
TIBCO EMS, CICS, SAP RFC, JDBC, Mongo, Databases,
OFX, IFX, RIXML, AS2,
Amazon Simple Notification Service, AWS IoT Message Broker, XMPP,
Google Cloud Messaging, Azure Event Grid, Azure Event Hubs,
Azure Service Bus, STOMP, Thrift, Avro, HTTP/2, LWM2M, CoAP, ZeroMQ, Broker-J, Qpid, QUIC and gQUIC
; ProprietaryHTTP
Wilma; GPL v3.0HTTP
Wiremock; Apache 2HTTP
WireMock.Net; Apache 2HTTP
Wiresham; Apache 2TCP