Best Contract Testing Tools in 2026
Updated
In short: oasdiff is ranked #1 of 22 as of 5 October 2026, ahead of Pact and Microcks. The best-ranked option with a free plan is Pact. The lowest first paid tier on this page is Specmatic at $1.67/mo.
When services depend on one another’s APIs, contract testing can help check that consumers and providers agree on expected behavior. Compared on contract formats, consumer and provider verification, and registry support, these tools also differ in AsyncAPI and GraphQL support. Self-hosted deployment, free-plan availability, and paid-from pricing add practical points to weigh. The 22 entries include oasdiff, Pact, and Microcks. Consider the formats and interfaces your team needs to validate, then compare the stated verification, registry, hosting, and cost details against those needs.
22 contract testing tools ranked on what their makers publish — plans and prices, free tiers, platforms and the facts on their own pages.
22ranked
14free plans on this page
$1.67/molowest paid tier
5 Oct 2026last checked
Input list Contract Testing Tools 22 channels on this page · 79 of 176 spec lines stated by the makers
Ch Tool Free planPaid fromContract formatsConsumer verificationProvider verificationContract registryAsyncAPI supportGraphQL support Spec sheet Score
01 oasdiff Free planYesPaid from$100/moContract formatsOpenAPI 3.0, OpenAPI 3.1, OpenAPI 3.2; JSON and YAMLConsumer verificationnot statedProvider verificationnot statedContract registrynot statedAsyncAPI supportNoGraphQL supportNo 5/8spec lines stated 7.8
02 Pact Free planYesPaid fromnot statedContract formatsnot statedConsumer verificationnot statedProvider verificationnot statedContract registrynot statedAsyncAPI supportnot statedGraphQL supportYes 2/8spec lines stated 7.8
03 Microcks Free planYesPaid fromnot statedContract formatsnot statedConsumer verificationnot statedProvider verificationnot statedContract registrynot statedAsyncAPI supportnot statedGraphQL supportnot stated 1/8spec lines stated 7.6
04 Pact Broker Free planYesPaid fromnot statedContract formatsPact JSON (HTTP and message interactions)Consumer verificationYesProvider verificationYesContract registryYesAsyncAPI supportnot statedGraphQL supportYes 6/8spec lines stated 7.5
05 Confluent Cloud Free planYesPaid from$385/moContract formatsnot statedConsumer verificationnot statedProvider verificationnot statedContract registrynot statedAsyncAPI supportnot statedGraphQL supportnot stated 2/8spec lines stated 7.4
06 GraphQL Hive Free planYesPaid fromnot statedContract formatsGraphQL schemas in GraphQL SDL formatConsumer verificationYesProvider verificationYesContract registryNoAsyncAPI supportnot statedGraphQL supportYes 6/8spec lines stated 7.3
07 Karate Free planYesPaid fromnot statedContract formatsnot statedConsumer verificationnot statedProvider verificationnot statedContract registrynot statedAsyncAPI supportnot statedGraphQL supportYes 2/8spec lines stated 7.3
08 Specmatic Free planYesPaid fromnot statedContract formatsnot statedConsumer verificationnot statedProvider verificationnot statedContract registrynot statedAsyncAPI supportnot statedGraphQL supportnot stated 1/8spec lines stated 7.3
09 PactFlow Free planYesPaid from$115.42/moContract formatsnot statedConsumer verificationnot statedProvider verificationnot statedContract registrynot statedAsyncAPI supportnot statedGraphQL supportNo 3/8spec lines stated 7.2
10 Apicurio Registry Free plannot statedPaid fromnot statedContract formatsOpenAPI, AsyncAPI, GraphQL, Apache Avro, Google Protobuf, JSON Schema, Kafka Connect, WSDL, XML Schema, ODCS v3.1Consumer verificationYesProvider verificationnot statedContract registryYesAsyncAPI supportYesGraphQL supportYes 5/8spec lines stated 7.1
11 Schemathesis Free planYesPaid fromnot statedContract formatsnot statedConsumer verificationnot statedProvider verificationnot statedContract registrynot statedAsyncAPI supportnot statedGraphQL supportYes 2/8spec lines stated 7.1
12 SpecShield Free planYesPaid from$75/moContract formatsOpenAPI (JSON/YAML), GraphQLConsumer verificationYesProvider verificationYesContract registryYesAsyncAPI supportnot statedGraphQL supportYes 7/8spec lines stated 7.0
13 Karapace Free planYesPaid fromnot statedContract formatsAvro, JSON Schema, ProtobufConsumer verificationNoProvider verificationNoContract registryYesAsyncAPI supportNoGraphQL supportNo 7/8spec lines stated 6.8
14 Stubborn Contract Free planYesPaid fromnot statedContract formatsYAML, Groovy, Java, KotlinConsumer verificationYesProvider verificationYesContract registryYesAsyncAPI supportnot statedGraphQL supportnot stated 5/8spec lines stated 6.8
15 WSO2 Contract Test Runner Free plannot statedPaid fromnot statedContract formatsJSONConsumer verificationYesProvider verificationYesContract registrynot statedAsyncAPI supportnot statedGraphQL supportnot stated 3/8spec lines stated 6.7
16 BitDive Free planYesPaid fromnot statedContract formatsJSON, XMLConsumer verificationnot statedProvider verificationYesContract registrynot statedAsyncAPI supportnot statedGraphQL supportnot stated 3/8spec lines stated 5.8
17 Entente Free plannot statedPaid fromnot statedContract formatsOpenAPIConsumer verificationYesProvider verificationYesContract registryYesAsyncAPI supportnot statedGraphQL supportnot stated 4/8spec lines stated 5.8
18 Signet Free plannot statedPaid fromnot statedContract formatsOpenAPI, PactConsumer verificationYesProvider verificationYesContract registryYesAsyncAPI supportnot statedGraphQL supportnot stated 4/8spec lines stated 5.8
19 API Contract Tester Free planYesPaid from$19/moContract formatsTypeScript, OpenAPI, JSONConsumer verificationnot statedProvider verificationnot statedContract registrynot statedAsyncAPI supportnot statedGraphQL supportnot stated 3/8spec lines stated 5.7
20 BBC Consumer Contracts Free planYesPaid fromnot statedContract formatsJavaScriptConsumer verificationYesProvider verificationnot statedContract registrynot statedAsyncAPI supportnot statedGraphQL supportnot stated 3/8spec lines stated 5.6
21 ContractCase Free plannot statedPaid fromnot statedContract formatsContractCase Case Files; JSON for HTTP contractsConsumer verificationYesProvider verificationYesContract registryNoAsyncAPI supportnot statedGraphQL supportnot stated 4/8spec lines stated 5.6
22 Citrus Free planYesPaid fromnot statedContract formatsnot statedConsumer verificationnot statedProvider verificationnot statedContract registrynot statedAsyncAPI supportnot statedGraphQL supportnot stated 1/8spec lines stated 5.2
Compare all 22 in a table
| # | Tool | Score | Free plan | From | Free plan | Paid from | Contract formats | Consumer verification |
|---|---|---|---|---|---|---|---|---|
| 1 | oasdiff | 7.8 | Free plan | $100/mo | Yes | 100 /mo | OpenAPI 3.0, OpenAPI 3.1, OpenAPI 3.2; JSON and YAML | — |
| 2 | Pact | 7.8 | Free plan | $115.42/mo | Yes | — | — | — |
| 3 | Microcks | 7.6 | Free plan | Free | Yes | — | — | — |
| 4 | Pact Broker | 7.5 | Free plan | $115.42/mo | Yes | — | Pact JSON (HTTP and message interactions) | Yes |
| 5 | Confluent Cloud | 7.4 | Free plan | $385/mo | Yes | 385 /mo | — | — |
| 6 | GraphQL Hive | 7.3 | Free plan | $20/mo | Yes | — | GraphQL schemas in GraphQL SDL format | Yes |
| 7 | Karate | 7.3 | Free plan | $8.33/mo | Yes | — | — | — |
| 8 | Specmatic | 7.3 | Free plan | $1.67/mo | Yes | — | — | — |
| 9 | PactFlow | 7.2 | Free plan | $115.42/mo | Yes | 115.42 /mo | — | — |
| 10 | Apicurio Registry | 7.1 | No | — | — | — | OpenAPI, AsyncAPI, GraphQL, Apache Avro, Google Protobuf, JSON Schema, Kafka Connect, WSDL, XML Schema, ODCS v3.1 | Yes |
| 11 | Schemathesis | 7.1 | Free plan | Free | Yes | — | — | — |
| 12 | SpecShield | 7.0 | Free plan | $89/mo | Yes | 75 /mo | OpenAPI (JSON/YAML), GraphQL | Yes |
| 13 | Karapace | 6.8 | Free plan | Free | Yes | — | Avro, JSON Schema, Protobuf | No |
| 14 | Stubborn Contract | 6.8 | Free plan | Free | Yes | — | YAML, Groovy, Java, Kotlin | Yes |
| 15 | WSO2 Contract Test Runner | 6.7 | Free plan | Free | — | — | JSON | Yes |
| 16 | BitDive | 5.8 | No | — | Yes | — | JSON, XML | — |
| 17 | Entente | 5.8 | No | — | — | — | OpenAPI | Yes |
| 18 | Signet | 5.8 | No | — | — | — | OpenAPI, Pact | Yes |
| 19 | API Contract Tester | 5.7 | No | — | Yes | 19 /mo | TypeScript, OpenAPI, JSON | — |
| 20 | BBC Consumer Contracts | 5.6 | No | — | Yes | — | JavaScript | Yes |
| 21 | ContractCase | 5.6 | No | — | — | — | ContractCase Case Files; JSON for HTTP contracts | Yes |
| 22 | Citrus | 5.2 | No | — | Yes | — | — | — |
Is your tool on this list?
Numbered spots on this list can be sponsored, and a sponsored row is labelled as paid.
Questions about this list
Which contract testing tool is ranked first on Specifiction?
oasdiff is ranked #1 of 22 with a score of 7.8. Pact is second and Microcks third.
How many of these have a free plan?
14 of the 22 on this page publish a free plan on their own pricing pages.
Which is the cheapest paid option?
On this page, Specmatic has the lowest first paid tier we found: $1.67/mo.
How is this list ranked?
Ranked on what each maker publishes, the fullest spec sheet first: how deeply the product is documented, the platforms it runs on, a free tier or trial to test it, and its standing.
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