# Appen vs clickworker Appen records 665,840 monthly visits with +0.2% month-over-month growth and Contact for Pricing pricing. clickworker records 1,861,149 monthly visits with +0.5% growth and Contact for Pricing pricing. | Metric | [Appen](https://openaitools.app/tool/appen-com) | [clickworker](https://openaitools.app/tool/clickworker-com) | | :--- | :--- | :--- | | Website URL | https://appen.com | https://clickworker.com | | Categories | AI Models, Large Language Models (LLMs), AI Developer Tools | AI Developer Tools, Large Language Models (LLMs), AI Face Recognition, AI Transcription | | Pricing Model | Contact for Pricing | Contact for Pricing | | Monthly Visits | 665,840 | 1,861,149 | | MoM Growth Rate | +0.2% | +0.5% | | Primary Market | United States | United States | | Direct Visits | 238,314 | 947,133 | | Review Score | 4.4 | 3.9 | | Saved Count | 2 | 3 | | Supported Platforms | Website | Website | ## Appen Appen is one of the oldest pure-play AI data companies, tracing its roots to 1996 when it began building human-labeled datasets for speech recognition and NLP. Over three decades it supported successive generations of model development — search relevance in the 2000s, machine translation, deep-learning vision annotation, Transformer-era semantics, GPT-3 scale corpora, RLHF for conversational AI, and now agentic and multimodal foundation models. Today Appen positions itself around six specialised capability areas: Frontier Alignment (chain-of-thought reasoning traces, SME RLHF, supervised fine-tuning demonstrations, adversarial red teaming), Agentic AI (golden trajectories, RL environment design, failure-mode taxonomies, SWE-driven evaluation), Multimodal and Speech AI (multilingual ASR and conversational corpora, expressive TTS annotation, VLM training data, video action labelling), Physical AI (LiDAR point-cloud annotation, multi-camera sensor fusion, robotics demonstration trajectories, world-model rollouts), Model Integrity (hallucination benchmarking, bias detection, regulatory audits and continuous monitoring), and Research Services (context engineering, calibrated LLM-as-a-judge, synthetic data and custom benchmarking). Delivery runs through Appen's AI Data Platform (ADAP), which blends automation with human oversight, and the company cites SOC 2 and ISO 27001 certification, 500+ global locales, and a client roster that includes major cloud, search, retail and aerospace organisations. Appen does not publish self-serve pricing; engagements start with a scoping conversation and are quoted per project, so cost depends on data volume, language coverage, modality and annotation complexity. **Pricing & Plans:** Enterprise/contact-for-pricing. Appen does not publish self-serve plans; projects are scoped and quoted individually. Appen also sells off-the-shelf (OTS) datasets and crowd/contractor workforce programs with separate terms. - **Frontier alignment data:** Chain-of-thought reasoning traces, SME-level RLHF, supervised fine-tuning demonstrations and adversarial red teaming for the most capable models. - **Agentic AI datasets:** Golden trajectories, RL environment design, failure-mode taxonomies and software-engineering-driven deep evaluation for autonomous agents. - **Multimodal and speech corpora:** Multilingual ASR and conversational speech data, expressive TTS annotation, vision-language model training data, video action labelling and voice-agent evaluation. - **Physical AI annotation:** LiDAR point-cloud labeling, multi-camera sensor fusion, robot demonstration trajectories, world-model rollouts and embodied interaction logs. - **Model integrity and evaluation:** Hallucination benchmarking, bias detection, regulatory audits and continuous monitoring, plus independent model evaluation. - **AI Data Platform (ADAP):** A production platform that combines automation with human oversight, with SOC 2 and ISO 27001 certification and 500+ locales covered. **Strengths:** Three decades of annotation methodology, tooling and workforce management experience; Very broad coverage: frontier alignment, agentic, speech, multimodal, physical AI and evaluation in one vendor; 500+ locales and multilingual expertise that most in-house teams cannot match; Enterprise-grade security posture (SOC 2, ISO 27001) and publicly listed governance **Limitations:** No transparent self-serve pricing; every engagement requires a sales/scoping cycle; Enterprise-oriented contracts can be heavy for small teams or indie developers; Quality depends on workforce management, so results vary by project and locale; Overlaps with many cheaper specialist annotation vendors, making vendor selection non-trivial [Profile (Markdown)](https://openaitools.app/tool/appen-com.md) ## clickworker clickworker is a data-services company that turns business data projects into structured microtasks carried out by a global crowd. Companies define a task — collecting shelf photos, labeling images, verifying addresses, running surveys, testing an app — and clickworker recruits, briefs and quality-checks the workers who complete it. The crowd numbers more than 10 million registered freelancers across 136 countries. The core offering is AI training data: image, video, audio and text datasets with human-powered labeling, annotation and validation, delivered in cooperation with parent company LXT. Around that sit adjacent services such as surveys with a verified respondent pool, store checks and display audits at the point of sale, tagging and sentiment analysis, crowdtesting for websites and apps, list building, and SEO copywriting. Engagements can be self-service, fully managed or delivered through an API and iframe integration. clickworker emphasizes its 20+ years of microtask experience, ISO 27001 certification and GDPR compliance, and works with clients such as OTTO, Bosch and Tennis-Point on large-scale data collection and evaluation projects. **Pricing & Plans:** clickworker quotes project prices rather than publishing list rates; cost depends on task type, volume, target geography and quality requirements. A self-service option and a managed service are both available, and Clickworkers are paid per completed task. - **AI training data at scale:** Custom image, video, audio and text datasets with human labeling, annotation and validation, delivered with parent company LXT. - **Global crowd of 10M+ Clickworkers:** Registered freelancers in 136 countries fill microtasks through web, Android and iOS apps, with flexible scaling up or down. - **Survey and market research services:** An all-in-one survey tool plus access to a verified respondent pool for external studies and targeted insights. - **Store checks and crowdtesting:** Real-time point-of-sale data collection, display audits, mystery checks, and usability testing for websites, apps and games. - **Managed, self-service and API delivery:** Choose a fully managed project, run tasks yourself, or integrate crowd workflows through API and iframe form options. **Strengths:** Enormous, geographically diverse crowd that can scale projects up or down quickly; Covers the full data pipeline from collection through annotation and validation; ISO 27001 certified and GDPR compliant with documented quality assurance; Multiple engagement models: managed, self-service, API and iframe **Limitations:** Pricing is quote-based, so smaller projects may struggle to get transparent costs; Quality depends on task design and briefing, which the client must invest effort in; Not a plug-and-play AI API — it is a services business requiring project scoping [Profile (Markdown)](https://openaitools.app/tool/clickworker-com.md) ## Frequently Asked Questions ### How do Appen and clickworker compare in monthly traffic? Appen has 665,840 monthly visits, while clickworker has 1,861,149. Traffic estimates describe audience size, not product quality. ### How do their growth rates compare? Appen has a month-over-month growth rate of +0.2%; clickworker has +0.5%. ### How does pricing compare? Appen: Contact for Pricing. Enterprise/contact-for-pricing. Appen does not publish self-serve plans; projects are scoped and quoted individually. Appen also sells off-the-shelf (OTS) datasets and crowd/contractor workforce programs with separate terms. clickworker: Contact for Pricing. clickworker quotes project prices rather than publishing list rates; cost depends on task type, volume, target geography and quality requirements. A self-service option and a managed service are both available, and Clickworkers are paid per completed task. ## Alternatives | # | Tool Name | Monthly Visits | MoM Growth Rate | Pricing Model | Summary | Profile (Markdown) | | :--- | :--- | :--- | :--- | :--- | :--- | :--- | | 1 | [Prolific](https://openaitools.app/tool/prolific-com) | 18,697,671 | -1.8% | Paid | Offers a high-quality pool of verified human participants for research and preference tuning, but is less focused on traditional data annotation. | [.md](https://openaitools.app/tool/prolific-com.md) | | 2 | [Outlier AI](https://openaitools.app/tool/outlier-ai) | 10,372,036 | +7.6% | Paid | Connects subject matter experts for advanced LLM training and prompting, but lacks general microtask crowdsourcing capabilities. | [.md](https://openaitools.app/tool/outlier-ai.md) | | 3 | [OpenTrain AI](https://openaitools.app/tool/opentrain-ai) | 1,469,348 | +11.2% | Contact for Pricing | Specializes in matching AI labs with vetted human experts for RLHF, but offers fewer general data annotation services. | [.md](https://openaitools.app/tool/opentrain-ai.md) | | 4 | [Invisible Technologies](https://openaitools.app/tool/invisible-technologies-inc) | 1,364,520 | +64.4% | Contact for Pricing | Blends custom software with dedicated human expert teams to handle complex operations, but operates as a bespoke service. | [.md](https://openaitools.app/tool/invisible-technologies-inc.md) | | 5 | [Labelbox](https://openaitools.app/tool/labelbox) | 762,803 | -22.8% | Contact for Pricing | Combines robust data labeling tools with automated workflows, but focuses more on software tooling than managed human workforces. | [.md](https://openaitools.app/tool/labelbox.md) | | 6 | [Scale](https://openaitools.app/tool/scale) | 616,915 | +12.5% | Contact for Pricing | Provides enterprise-grade AI training data and model evaluation at massive scale, but often with higher enterprise pricing. | [.md](https://openaitools.app/tool/scale.md) | | 7 | [SuperAnnotate](https://openaitools.app/tool/super-annotate) | 386,034 | +37.4% | Free Trial, Contact for Pricing | Delivers advanced multimodal data curation and annotation infrastructure, but requires your own annotation workforce for labeling tasks. | [.md](https://openaitools.app/tool/super-annotate.md) | | 8 | [Arize AI](https://openaitools.app/tool/arize-com) | 249,028 | +3.2% | Paid, Contact for Pricing | Agent observability, evaluation, and continuous improvement for production AI | [.md](https://openaitools.app/tool/arize-com.md) | | 9 | [Surge AI](https://openaitools.app/tool/surgehq-ai) | 245,142 | +6.6% | Contact for Pricing | Focuses on elite domain experts for complex RLHF and frontier AI evaluation, but lacks casual crowdsourcing tasks. | [.md](https://openaitools.app/tool/surgehq-ai.md) | | 10 | [Encord](https://openaitools.app/tool/encord-com) | 244,204 | +9.4% | Contact for Pricing | The multimodal data layer for computer vision and physical AI teams | [.md](https://openaitools.app/tool/encord-com.md) | --- Source: https://openaitools.app/compare/appen-com-vs-clickworker-com More Markdown: [Categories](https://openaitools.app/categories.md) · [Traffic rankings](https://openaitools.app/rankings.md) · [llms.txt](https://openaitools.app/llms.txt)