Testing & mock-data tools

This hub collects the developer tools for testing and mock data — realistic fake users, API responses, database records, payloads, and the test cases to exercise them. Everything runs in your browser with no real personal data involved, so you can seed dev environments and write tests without touching production. Pick a tool below.

159 tools in this collection

API Test Case Generator

Checklist of test cases for an API endpoint

ListHTTP method

Basic Auth Credentials Generator

HTTP Basic Auth credentials with the matching base64 Authorization header

cURL Command Builder

Ready-to-run curl command from a method, URL, and headers

TextHTTP methodURL

cURL Command Generator

Example curl commands for any HTTP method to use in docs, tests, and learning

TextHTTP method

Dummy Address Generator (Developer)

Realistic fake postal addresses for testing and mock data

ListHow manyCountry

Dummy Bearer Token Generator

Realistic-looking dummy Bearer tokens for API testing and mock auth

ListHow ManyToken Length

Dummy Changelog Entry Generator

Realistic fake CHANGELOG entries in Keep a Changelog format for testing and demos

TextNumber of VersionsProject Type

Dummy CI Build Log Generator

Realistic fake CI/CD build logs for testing, demos, and documentation

TextBuild ResultCI System

Dummy CIDR Block Generator

Random CIDR notation IP address blocks for network configuration testing

ListHow ManyIP Version

Dummy Config File Generator

Realistic dummy configuration files in JSON, YAML, and TOML formats for app testing

TextConfig FormatApp Type

Dummy cURL Command Generator

Realistic cURL commands for REST API testing and documentation

ListHow manyHTTP Method

Dummy Git Commit Message Generator

Realistic fake git commit messages for testing, demos, and history mocking

TextNumber of commitsCommit style

Dummy GraphQL Variables Generator

Mock GraphQL variables JSON objects for query and mutation testing

ListOperation TypeHow Many

Dummy HTML Snippet Generator

Realistic HTML code snippets for testing, demos, and placeholder content

TextSnippet TypeItems / Rows

Dummy JSON Array Generator

Arrays of fake JSON objects with configurable fields for API mocking and testing

TextNumber of RecordsSchema Type

Dummy JWT Generator

Realistic-looking but fake JSON Web Tokens for testing token handling

Dummy Kubernetes Manifest Generator

Mock Kubernetes YAML manifests for Deployments, Services, and ConfigMaps

TextApp NameResource Kind

Dummy Linux Username Generator

Realistic Linux-style usernames for system, server, and DevOps testing

ListHow manyStyle

Dummy Markdown Table Generator

Filled Markdown table for documentation and testing

Dummy OpenTelemetry Trace Generator

Mock distributed tracing spans and trace payloads in OpenTelemetry format

ListNumber of SpansService Name

Dummy Phone Number Generator

Fake but realistically formatted phone numbers for testing

ListHow manyFormat

Dummy SSH Key Pair Generator

Realistic-looking fake SSH public key strings for testing and documentation

ListHow ManyKey Type

Dummy Stack Trace Generator

Realistic fake stack traces for multiple languages to test error UIs

TextLanguageStack Depth

Dummy Test Case Generator

Boilerplate unit test cases in popular testing frameworks for faster TDD setup

ListNumber of test casesFramework

Dummy User Bio Generator

Short placeholder user bios for profile mockups and test data

Dummy YAML Config Generator

Realistic dummy YAML configuration file for testing

Error Message Generator

Realistic HTTP error codes and messages for testing and mocks

Fake API Key Generator

Realistic-looking fake API keys in common formats for testing and documentation

ListNumber of keysKey format

Fake Browser Cookie Generator

Realistic fake HTTP browser cookies for testing and development

ListNumber of CookiesInclude Secure/HttpOnly flags

Fake Browser Fingerprint Generator

Realistic mock browser fingerprint data objects for testing and QA

Fake Commit Message Generator

Realistic conventional-commit messages for test repos and demos

Fake Company Email Generator

Realistic fake company email addresses for testing and development

ListHow manyDomain (leave blank for random)

Fake Credit Card Generator

Fake but structurally valid credit card numbers for testing payment forms

ListHow manyCard Network

Fake Domain & URL Generator

Realistic fake domain names and full URLs for testing and placeholder content

ListHow ManyURL Type

Fake Email Address Generator

Realistic-looking fake email addresses for testing and development

ListHow manyDomain style

Fake Email Generator

Realistic-looking fake email addresses for testing and development

ListHow manyDomain style

Fake Error Stack Trace Generator

Realistic fake error stack traces for testing error handling and logging systems

TextLanguageStack Depth

Fake GitHub Repository Generator

Realistic mock GitHub repository metadata for demos and testing

ListNumber of ReposPrimary Language

Fake GraphQL Query Generator

Realistic fake GraphQL queries and mutations for testing and documentation

TextResource / type nameOperation type

Fake Hash Generator

Realistic fake hash strings in MD5, SHA-1, SHA-256, and bcrypt formats

ListNumber of HashesHash Type

Fake IP Address Generator

Random fake IPv4 and IPv6 addresses for testing

ListVersionHow many

Fake ISBN Generator

Valid-format fake ISBN-13 numbers for testing and placeholder data

Fake JWK Generator

Fake JSON Web Key object for testing JWT and key-handling code

Fake JWT Payload Generator

Realistic mock JWT payloads with common claims for testing and development

ListHow manyUser Role

Fake License Key Generator

Fake software license keys in common formats for testing activation flows

Fake Log Entry Generator

Realistic application log lines for testing log parsers and dashboards

ListNumber of LinesLog Format

Fake Log Entry Generator (Line)

Realistic application and server log lines for testing log parsers and dashboards

ListNumber of linesLog format

Fake Mobile Device Info Generator

Realistic fake mobile device metadata including model, OS, screen size, and specs

ListPlatformHow Many

Fake Network Packet Generator

Mock network packet metadata for networking education and testing

ListProtocolNumber of Packets

Fake OAuth Token Generator

Fake OAuth 2.0 access tokens, refresh tokens, and full token responses for API testing

ListHow manyOutput Format

Fake Secure Token Generator

Random high-entropy tokens for API keys, secrets, and testing

ListFormatHow many

Fake TCP/IP Packet Info Generator

Mock TCP/IP packet metadata for network testing and education

ListNumber of PacketsProtocol

Fake Transaction ID Generator

Realistic fake transaction and payment IDs for testing payment flows

Fake Webhook Event Generator

Realistic mock webhook event payloads for testing integrations

ListEvent TypeNumber of Events

Fake XML Data Generator

Realistic fake XML data structures for testing and development

TextNumber of RecordsRoot Tag Name

Fake XML Payload Generator

Realistic fake XML payloads for API testing and development

TextRoot Element NameNumber of Records

GraphQL Resolver Mock Generator

Mock GraphQL resolver functions with realistic type signatures and return values

ListNumber of ResolversStyle

HTTP Status Code Explainer

Explains a random HTTP status code in depth — meaning, when to use it, and an example

TextStatus class

HTTP Status Code Explainer (Developer)

Explains an HTTP status code and when to use it

TextStatus code

HTTP Status Code Reference Generator

Random HTTP status code with its correct name and meaning

JWT Token Generator

Realistic fake JWT tokens for testing and development

TextSubject (user ID)Role

Mock .env File Generator

Fake environment variable file for testing and documentation

Mock .gitignore Generator

Example .gitignore file for common project types

Mock API Response Generator

Realistic fake JSON API responses with configurable fields for frontend development

TextResource typeItems in response

Mock AWS ARN Generator

Realistic fake AWS ARN strings for IAM policies, testing, and documentation

ListAWS ServiceHow Many

Mock CI Pipeline Config Generator

Example CI pipeline YAML config for testing and learning

Mock CI/CD Pipeline Config Generator

Realistic mock CI/CD pipeline configuration files for popular platforms

TextCI/CD PlatformProject Type

Mock CLI Command Generator

Realistic fake CLI commands for documentation, tutorials, and shell script testing

ListNumber of commandsCLI tool

Mock Cloud Resource ID Generator

Fake AWS, GCP, and Azure resource identifiers for testing and demos

ListCloud ProviderNumber of IDs

Mock Cookie Header Generator

Example Set-Cookie header values with realistic attributes

Mock CSP Header Generator

Example Content-Security-Policy headers for web security

Mock CSV Data Generator

Realistic mock CSV data with headers and rows for testing and development

TextNumber of RowsFields to Include

Mock Database Connection String Generator

Fake database connection strings for common databases

Mock Database Migration Generator

Dummy SQL up/down migration scripts for schema changes and testing

TextTable NameMigration Type

Mock Database Record Generator

Mock SQL-ready database records with realistic field values for multiple table types

ListNumber of recordsTable Type

Mock Database Schema Generator

Realistic fake SQL table schemas with fields, types, and constraints for prototyping

TextTable NameSQL Dialect

Mock Device ID Generator

Fake device identifiers and MAC-style addresses for testing

ListFormatHow many

Mock DNS Record Generator

Example DNS records with matching types and values for testing

Mock Docker Compose Generator

Realistic docker-compose.yml files for common development stack configurations

TextDatabaseInclude Redis Cache

Mock Dockerfile Generator

Example Dockerfile for containerizing an application

Mock EditorConfig Generator

Example .editorconfig file to standardize coding styles

TextIndent style

Mock Elasticsearch Query Generator

Example Elasticsearch query DSL JSON for testing and learning

Mock Error Log Generator

Realistic application error log lines for testing log parsers and monitoring tools

ListNumber of log linesLog level

Mock Error Message Generator

Realistic stack traces and error messages for testing error handling UI

TextLanguage / RuntimeError Type

Mock Event Sourcing Payload Generator

Realistic domain event payloads in event sourcing and CQRS patterns

ListNumber of EventsDomain

Mock Feature Flag Config Generator

Realistic fake feature flag configuration objects for testing feature toggle systems

TextNumber of FlagsOutput Format

Mock Feature Flag Name Generator

Conventional feature flag names for testing flag systems and configs

Mock Feature Flag Rollout Generator

Example feature-flag rollout configurations as JSON

Mock Form Data Generator

Realistic fake form field values including names, emails, phones, and addresses

ListNumber of form entriesOutput format

Mock GraphQL Error Generator

Realistic GraphQL error response payloads for testing error handling

TextNumber of ErrorsError Category

Mock GraphQL Mutation Generator

Realistic fake GraphQL mutation strings for testing GraphQL APIs and clients

TextMutation TypeNumber of Mutations

Mock GraphQL Query Generator

Realistic GraphQL queries and mutations for testing and prototyping

ListHow manyOperation Type

Mock GraphQL Response Generator

Realistic fake GraphQL JSON responses for frontend and API testing

TextEntity TypeResult Count

Mock GraphQL Schema Generator

Realistic mock GraphQL schemas with types, queries, and mutations

TextEntity NameNumber of Fields

Mock GraphQL Schema Snippet Generator

Example GraphQL type definitions for testing and prototyping

Mock gRPC Proto Message Generator

Realistic fake Protocol Buffer message definitions and sample JSON representations

TextService NameMessage Type

Mock HTTP Header Generator

Realistic fake HTTP request headers for API testing and development

ListNumber of header setsRequest Type

Mock HTTP Request Generator

Example raw HTTP requests for testing and learning

Mock HTTP Response Body Generator

Realistic fake HTTP JSON response bodies for common API patterns

TextResponse PatternResource Name

Mock HTTP Status Response Generator

Mock HTTP responses with status codes, headers, and JSON bodies for API testing

ListStatus GroupHow many

Mock Jenkinsfile Generator

Example declarative Jenkins pipeline for CI/CD

Mock JSON Data Generator

Structured mock JSON objects for API testing and prototyping

TextNumber of recordsData schema

Mock JSON Payload Generator

Random nested JSON payloads for API testing and webhook simulation

TextPayload typeNumber of payloads

Mock JWT Token Generator

Realistically structured but fake JSON Web Tokens for testing

Mock Kafka Message Generator

Realistic fake Apache Kafka messages with headers, key, and JSON payload

ListTopic NameEvent Type

Mock Kubernetes Manifest Generator

Example Kubernetes YAML manifests for learning and testing

Mock License Header Generator

Source-file license header comments in common formats

Mock Makefile Generator

Example Makefile with common build and run targets

Mock Network Config Generator

Fake but realistic network configuration blocks including IPs, subnets, and gateways

ListNumber of configsConfig type

Mock Nginx Config Generator

Example nginx server block configurations for testing

Mock OAuth Token Response Generator

Realistic fake OAuth 2.0 token response as JSON for testing

Mock OAuth2 Flow Data Generator

Realistic OAuth2 authorization codes, tokens, and flow payloads for testing

ListOAuth2 FlowNumber of Samples

Mock OpenAPI Spec Generator

Minimal but valid OpenAPI 3.0 specification YAML document for a given resource

TextResource NameAPI Title

Mock package.json Generator

Example package.json manifest for a Node project

Mock Pagination Link Generator

Mock REST pagination links (first, prev, next, last) for API testing

TextCurrent page

Mock Pagination Metadata Generator

Realistic API pagination metadata blocks for frontend and backend testing

ListFormatHow Many

Mock Pagination Response Generator

Realistic paginated API JSON responses with metadata for frontend and backend testing

TextItems per PageCurrent Page

Mock Postgres Query Generator

Example SQL SELECT queries with joins and filters for testing

Mock Postgres Table Schema Generator

Example PostgreSQL CREATE TABLE statements for testing

Mock Prometheus Metric Generator

Example Prometheus-format metrics for testing and dashboards

Mock RabbitMQ Message Generator

Fake message-queue payloads with routing metadata for testing

Mock Rate Limit Header Generator

Example API rate-limit response headers for testing

Mock Rate Limit Response Generator

Realistic HTTP rate-limiting response headers and JSON bodies for API testing

ListNumber of ResponsesOutput Format

Mock Redis Command Generator

Example Redis commands for learning and testing

Mock Redis Key-Value Generator

Realistic Redis SET/GET commands with fake keys and values for testing

ListNumber of EntriesKey Namespace

Mock REST API Endpoint List Generator

Complete list of RESTful API endpoints with methods, paths, and descriptions for a given resource

TextResource NameAPI Version

Mock REST Endpoint Generator

Dummy REST API endpoint definitions with methods, paths, and responses

TextResource nameNumber of endpoints

Mock robots.txt Generator

Example robots.txt files to guide search engine crawlers

Mock S3 Bucket Name Generator

Valid, realistic object-storage bucket names for testing

Mock SaaS Pricing Plan Generator

Fake SaaS pricing plan data in JSON format for UI prototyping and testing

TextNumber of PlansCurrency

Mock Server-Sent Event Generator

Example Server-Sent Events (SSE) streams for testing

TextHow many events

Mock Sitemap XML Generator

Example XML sitemaps for search engines

Mock SOAP Envelope Generator

Example SOAP XML envelopes for testing legacy web services

Mock Stripe Event Generator

Fake Stripe-style webhook event payloads as JSON for testing

Mock Syslog Line Generator

Example syslog-format log lines for testing log pipelines

Mock Terminal Output Generator

Fake but realistic terminal/CLI output for demos, screenshots, and documentation

TextScenarioOutput Lines

Mock Terraform Resource Generator

Example Terraform resource blocks for learning and testing

Mock TOML Config Generator

Realistic fake TOML configuration files for app development and testing

TextApp NameSections to Include

Mock User Data Generator

Complete fake user profiles as JSON objects for API and database testing

TextNumber of usersOutput format

Mock User Profile Generator

Complete fake user profiles with name, email, phone, job, and more

ListHow many profilesOutput format

Mock User-Agent String Generator

Realistic browser user-agent strings for testing and mock requests

Mock Webhook Payload Generator

Realistic mock webhook payloads for common services like GitHub, Stripe, and Slack

ListServiceHow many

Mock Webhook Signature Generator

Example signed webhook headers for testing signature verification

Mock WebSocket Message Generator

Realistic fake WebSocket JSON message payloads for testing real-time apps

ListNumber of MessagesEvent Domain

Mock XML Config Generator

Realistic XML configuration files for testing and development

TextApp NameConfig Entries

Mock YAML Config Generator

Realistic YAML configuration files for apps, services, and environments

TextApp NameEnvironment

Random API Key Generator

Secure-looking random API keys in various formats for development and testing

ListNumber of KeysKey Format

Random API Key Generator (Developer)

Random API keys in common formats for development and testing

ListHow manyKey style

Random Emoji Shortcode Generator

Random emoji shortcodes for testing chat, markdown, and emoji pickers

Random HTTP Status Code Generator

Random HTTP status code with its name and meaning for testing and learning

TextStatus class

Random Port & Service Generator

Random network port numbers with associated service names for dev and testing configs

ListHow ManyPort Range

Random Semver Version Generator

Valid semantic version numbers for testing release tooling and changelogs

ListHow manyInclude pre-release tags

Random Test Data Name Generator

Realistic fake names, usernames, and display names for use in automated tests and mock data

ListNumber of NamesName Format

Random User Agent Generator

Realistic random User-Agent strings for browsers, bots, and mobile devices

ListHow manyDevice Type

Realistic Error Message Generator

Realistic error messages across common languages and systems

Semantic Version Generator

Valid semantic version numbers including pre-release and build tags

Unit Test Case Generator

Jest-style test skeleton with placeholder cases for a function

TextFunction nameNumber of cases

UUID v4 Generator

Random RFC 4122 version 4 UUIDs for testing and development

Webhook Payload Generator

Realistic JSON webhook payloads for building and testing webhook handlers

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