Data Annotation Freelance Jobs

Data annotation freelance jobs are projects where specialists label and evaluate training data for AI/ML systems. On Rex.zone, you’ll work on RLHF tasks, data labeling, QA evaluation, prompt evaluation, named entity recognition, computer vision annotation, content safety labeling, and large language model evaluation that feed LLM training pipelines. These roles improve training data quality, ensure annotation guidelines compliance, and drive model performance improvement across NLP, vision, and safety domains. Apply to remote, contract, and part-time engagements with AI labs, tech startups, BPOs, and annotation vendors through our platform.

Key Responsibilities

Create high-quality labels for text, image, video, and audio datasets; perform RLHF and LLM prompt/response evaluation; execute named entity recognition, taxonomy mapping, sentiment and intent tagging; conduct computer vision annotation (bounding boxes, polygons, keypoints, segmentation); handle content safety labeling with policy adherence; run QA evaluation, error analysis, and guideline refinement; document edge cases; collaborate with reviewers to improve training data quality and model performance improvement.

Required Qualifications

Strong attention to detail and consistency; ability to follow detailed annotation guidelines; excellent written communication; familiarity with NLP concepts (NER, sentiment, summarization), large language model evaluation, and/or computer vision tasks; experience with quality control (gold sets, inter-annotator agreement); comfortable with productivity targets and feedback cycles; reliable internet and secure work environment; willingness to sign NDAs and complete security training.

Tools & Platforms

Hands-on experience with annotation tools and pipelines such as Label Studio, Prodigy, CVAT, and internal labeling systems; use QA dashboards, rubric checklists, and review queues; follow rater calibration procedures; track issues via tickets; ensure annotation guidelines compliance and consistent taxonomies across projects.

Workflows at Rex.zone

Rex.zone routes tasks via calibrated queues with gold standards, consensus checks, and hierarchical review. You’ll participate in RLHF rater assignments, prompt evaluation, adversarial red-teaming, and quality audits. Feedback loops connect annotators, reviewers, and ML engineers to iteratively improve datasets powering LLM training pipelines.

Engagement Types & Modifiers

We staff remote, contract, freelance, part-time, and full-time roles across entry-level and senior tracks. Opportunities span short-term sprints, ongoing programs, and specialized expert reviews for regulated or domain-specific data.

Domains We Staff

NLP (NER, sentiment, summarization, classification), computer vision (detection, segmentation), multimodal evaluation, content safety and policy labeling, LLM prompt and response evaluation, search relevance, speech/audio labeling, and domain-specific datasets (medical, legal, finance).

How to Apply on Rex.zone

Create your Rex.zone profile, note your domains (NLP, computer vision, content safety), list tools you know, and complete a short calibration test. Qualified candidates join project pools with task notifications for AI labs, tech startups, BPOs, and annotation vendors.

Success Metrics & Quality

We track accuracy, precision/recall where applicable, inter-annotator agreement, throughput, latency SLAs, and policy compliance. Annotators receive rubric-based feedback and targeted coaching to continually lift training data quality.

Applying and Working on Rex.zone

Q: How do I apply?
Sign up on Rex.zone, complete your profile, select domains and tools, and pass a short calibration test. You’ll then be eligible for remote contract pools.
Q: How is compensation structured?
Compensation may be per task, hour, or project depending on the program. Details are shown before you accept work.
Q: How is quality measured?
We measure accuracy, inter-annotator agreement, guideline adherence, and throughput. Consistent high quality unlocks more complex projects.
Q: What about data security?
Most programs require NDAs, secure environments, and adherence to content and privacy policies. Some projects use VDI with restricted clipboard/downloads.
Q: How fast is onboarding?
After profile completion and calibration, many contributors start within days, depending on project demand and domain fit.

230+Domains Covered

120K+PhD, Specialist, Experts Onboarded

50+Countries Represented

Industry-Leading Compensation

We believe exceptional intelligence deserves exceptional pay. Our platform consistently offers rates above the industry average, rewarding experts for their true value and real impact on frontier AI. Here, your expertise isn't just appreciated—it's properly compensated.

Work Remotely, Work Freely

No office. No commute. No constraints. Our fully remote workflow gives experts complete flexibility to work at their own pace, from any country, any time zone. You focus on meaningful tasks—we handle the rest.

Respect at the Core of Everything

AI trainers are the heart of our company. We treat every expert with trust, humanity, and genuine appreciation. From personalized support to transparent communication, we build long-term relationships rooted in respect and care.

Ready to Shape the Future of Data Annotation & Labeling?

Apply Now.