Appen records 665,840 monthly visits with +0.2% month-over-month growth and Contact for Pricing pricing. Postman records 1,764,877 monthly visits with -7.6% growth and Freemium pricing.
Human-validated training data and evaluation services for frontier AI models
Design, test, and govern APIs — now with AI agents in the loop
| Dimension / Metric | | |
|---|---|---|
| Official Domain | appen.com | postman.com |
| Pricing Model | Contact for Pricing | Freemium |
| Monthly Visits | 665.84K (665,840) | 1.76M (1,764,877) |
| MoM Traffic Delta | +1.1K (+0.2%) | -144.52K (-7.6%) |
| Primary Market & Share | 🇺🇸 United States (22%) | 🇮🇳 India (22.9%) |
| Direct Visits / mo | 238.31K | 580.23K |
| User Rating | 4.4 | 4.7 |
| Supported Platforms | Website | Website |
Human-validated training data and evaluation services for frontier AI models
Chain-of-thought reasoning traces, SME-level RLHF, supervised fine-tuning demonstrations and adversarial red teaming for the most capable models.
Golden trajectories, RL environment design, failure-mode taxonomies and software-engineering-driven deep evaluation for autonomous agents.
Multilingual ASR and conversational speech data, expressive TTS annotation, vision-language model training data, video action labelling and voice-agent evaluation.
LiDAR point-cloud labeling, multi-camera sensor fusion, robot demonstration trajectories, world-model rollouts and embodied interaction logs.
Design, test, and govern APIs — now with AI agents in the loop
A multi-protocol client with collections, environments, variables, and reusable requests that works for local debugging and for driving automated test suites.
Generates assertions automatically, supports data-driven runs with exported datasets, and executes tests locally, in the cloud, or from CI pipelines via the Postman CLI.
Agent Mode, the Postman CLI agent skills, and a Model Context Protocol server let coding assistants build collections, write tests, and trigger API workflows from inside the editor.
A structured, queryable map of an organization's APIs, collections, and dependencies that lets agents find the right service and understand what a schema change would break.
SpecialistConnects teams directly with verified human participants for preference tuning and studies, but lacks managed end-to-end labeling pipelines.
SpecialistConnects teams directly with verified human participants for preference tuning and studies, but lacks managed end-to-end labeling pipelines.
SpecialistIntegrates API testing and development directly inside your code editor, but lacks Postman's dedicated workspace collection management and documentation publishing.
SpecialistIntegrates API testing and development directly inside your code editor, but lacks Postman's dedicated workspace collection management and documentation publishing.
SpecialistExcels at autonomous multi-file code generation and repository-wide understanding, but is not purpose-built for manual API endpoint testing.
SpecialistExcels at autonomous multi-file code generation and repository-wide understanding, but is not purpose-built for manual API endpoint testing.
Free / Open-sourcePowerful visual workflow automation and API integration builder, but lacks Postman's granular API request inspection and documentation features.
Free / Open-sourcePowerful visual workflow automation and API integration builder, but lacks Postman's granular API request inspection and documentation features.
Blends custom software with dedicated human expert teams to handle complex operations, but operates as a bespoke service.
Blends custom software with dedicated human expert teams to handle complex operations, but operates as a bespoke service.
Free / Open-sourceOpen-source control plane for orchestrating coding agents
SpecialistAutomates end-to-end testing using plain language agents, but lacks Postman's manual debugging and environment variable management tools.
Combines robust data labeling tools with automated workflows, but focuses more on software tooling than managed human workforces.
Combines robust data labeling tools with automated workflows, but focuses more on software tooling than managed human workforces.
Provides enterprise-grade AI training data and model evaluation at massive scale, but often with higher enterprise pricing.
Provides enterprise-grade AI training data and model evaluation at massive scale, but often with higher enterprise pricing.
Delivers advanced multimodal data curation and annotation infrastructure, but requires your own annotation workforce for labeling tasks.
Delivers advanced multimodal data curation and annotation infrastructure, but requires your own annotation workforce for labeling tasks.
SpecialistOffers superior test case management and CI integration for QA workflows, but lacks native API request crafting and mocking tools.
SpecialistOffers superior test case management and CI integration for QA workflows, but lacks native API request crafting and mocking tools.
SpecialistAgent observability, evaluation, and continuous improvement for production AI
SpecialistAgent observability, evaluation, and continuous improvement for production AI
