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Online Annotation Jobs in California (NOW HIRING)

Senior Perception Engineer

San Mateo, CA ยท On-site

$150 - $210/hr

Build full-body pose estimation systems for motion capture and teleoperation action annotation ... online recalibration) * Build visual SLAM / V-SLAM systems supporting real-time localization and ...

New

Machine learning, natural language processing, learning-to-rank, online learning, deep learning ... Coordinate data collection and annotation efforts. * Work with real-time data and content coming ...

Machine learning, natural language processing, learning-to-rank, online learning, deep learning ... Coordinate data collection and annotation efforts. * Work with real-time data and content coming ...

Build rigorous offline and online evaluations that measure task completion, accuracy, safety ... Create and maintain representative datasets from simulations, human annotation, production feedback ...

AI Modeling Engineer

Los Altos, CA ยท On-site

$140 - $210/hr

Build rigorous offline and online evaluations that measure task completion, accuracy, safety ... Create and maintain representative datasets from simulations, human annotation, production feedback ...

Build rigorous offline and online evaluations that measure task completion, accuracy, safety ... Create and maintain representative datasets from simulations, human annotation, production feedback ...

AI Modeling Engineer

Los Altos, CA ยท On-site

$140 - $200/hr

Build rigorous offline and online evaluations that measure task completion, accuracy, safety ... Create and maintain representative datasets from simulations, human annotation, production feedback ...

Senior AI/ML Engineer - Agentic AI

Newport Beach, CA ยท On-site

$112K - $154K/yr

Define the team's evaluation strategy: offline/online harnesses, trajectory quality, tool-call ... Human-in-the-loop annotation workflows at scale Agent frameworks and orchestration (production ...

Define the team's evaluation strategy: offline/online harnesses, trajectory quality, tool-call ... Human-in-the-loop annotation workflows at scale * Agent frameworks and orchestration(production ...

Senior AI/ML Engineer - Agentic AI

Newport Beach, CA ยท On-site

$112K - $153K/yr

Define the team's evaluation strategy: offline/online harnesses, trajectory quality, tool-call ... Human-in-the-loop annotation workflows at scale Agent frameworks and orchestration (production ...

Online Annotation information

See California salary details

$38.5K

$44.4K

$48.9K

How much do online annotation jobs pay per year?

As of Aug 25, 2026, the average yearly pay for online annotation in California is $44,410.00, according to ZipRecruiter salary data. Most workers in this role earn between $41,900.00 and $46,900.00 per year, depending on experience, location, and employer.

What is an online annotation?

An Online Annotation job involves labeling or tagging data such as images, text, audio, or video to help train machine learning models. Annotators follow specific guidelines to ensure accuracy and consistency in the data. These jobs are crucial in AI development, improving the quality of automated systems like image recognition, speech processing, and natural language understanding. Many online annotation jobs are remote and require attention to detail, basic computer skills, and sometimes domain-specific knowledge.

What are the key skills and qualifications needed to thrive in online annotation, and why are they important?

To excel in Online Annotation, strong attention to detail, proficiency in data labeling, and a solid understanding of guidelines for data quality are essential, often requiring at least a high school diploma or equivalent. Familiarity with annotation platforms, database tools, and sometimes basic knowledge of machine learning concepts is advantageous. Reliability, time management, and the ability to follow specific instructions set apart top performers in this role. These skills are crucial for providing high-quality, consistent data that supports training and validation of AI systems.

What are some common challenges faced by online annotation professionals, and how can they be managed?

A common challenge in Online Annotation is maintaining accuracy and consistency across large volumes of data, especially when guidelines are complex or frequently updated. To address this, professionals often need to regularly review instructions and participate in feedback sessions or quality audits provided by their employer. Staying organized, managing workload efficiently, and asking for clarification when uncertain can help minimize errors. Employers may provide training sessions or support forums to help annotators improve their skills and keep up-to-date with best practices.

What are the most commonly searched types of Annotation jobs in California?

The most popular types of Annotation jobs in California are:

What are popular job titles related to Online Annotation jobs in California?

For Online Annotation jobs in California, the most frequently searched job titles are:

What job categories do people searching Online Annotation jobs in California look for?

The top searched job categories for Online Annotation jobs in California are:

What cities in California are hiring for Online Annotation jobs?

Cities in California with the most Online Annotation job openings:

Infographic showing various Online Annotation job openings in California as of August 2026, with employment types broken down into 68% Full Time, 29% Part Time, 1% Temporary, and 2% Contract. Highlights an 80% Physical, 1% Hybrid, and 19% Remote job distribution, with an average salary of $44,410 per year, or $21.4 per hour.

Senior Perception Engineer

xdof, Inc.

San Mateo, CA โ€ข On-site

$150 - $210/hr

Other

Posted yesterday

New


Job description

At XDOF, we're at an inflection point. Frontier labs are racing to build general-purpose robots, and high-quality training data is the bottleneck. We're building the foundation behind the foundation models - the data collection systems, operational capability, exabyte-scale data warehouse, and software toolchain - to help our partners drive the field forward.

The Perception Algorithm team transforms raw multimodal sensor data into high-quality robot training annotations. You will be deeply involved in the complete loop from data collection to model delivery - sensor calibration, SLAM localization, human pose estimation, perception model training, and embedded deployment. Your work directly determines the quality ceiling of our training data.

Core Responsibilities Human Pose Estimation
  • Design and optimize hand pose estimation pipelines supporting accurate joint angle extraction from teleoperation data collection
  • Build full-body pose estimation systems for motion capture and teleoperation action annotation ground truth generation
  • Research and apply vision-based pose estimation methods (markerless) to reduce data collection costs
  • Fuse pose estimation outputs with robot joint angle data to generate consistent training annotations
Robot Perception & Calibration
  • Design and maintain intrinsic/extrinsic calibration pipelines for multi-camera arrays (factory calibration + online recalibration)
  • Build visual SLAM / V-SLAM systems supporting real-time localization and scene reconstruction on data collection platforms
  • Implement hand-eye calibration between cameras and robot end-effectors
  • Develop temporal alignment solutions across multimodal sensors (cameras, IMU, data gloves, force sensors)
Perception Model Training & Deployment
  • Train and iterate on perception models including object detection, instance segmentation, and 6DoF pose estimation
  • Optimize model inference using TensorRT / CUDA for real-time performance on robot embedded platforms
  • Write custom CUDA kernels for low-level acceleration of perception tasks
  • Design evaluation metric frameworks for perception models; continuously track the relationship between model performance and data quality
End-to-End Loop from Data Collection to Model Delivery
  • Contribute to the design of automated annotation pipelines that convert sensor data into structured training labels
  • Build Auto QA modules to filter low-quality data including anomalous frames, failed demonstrations, and sensor dropouts
  • Collaborate with ML engineers and data infrastructure teams to ensure perception output formats meet downstream VLA model training requirements
  • Establish feedback mechanisms linking perception accuracy to model training outcomes, continuously improving annotation quality
Requirements Must-Have
  • 5+ years of industry experience in robot perception or computer vision
  • Strong 3D vision fundamentals: stereo and structured-light camera principles, 3D reconstruction
  • Proficiency with SLAM frameworks (ORB-SLAM, VINS-Mono, FastLIO, etc.) or V-SLAM system development experience
  • Hands-on engineering experience with human pose estimation: hand joints (MediaPipe, MANO) or full-body pose (OpenPose, SMPLify, etc.)
  • Proficient in deep learning training frameworks for perception model training, tuning, and evaluation
  • TensorRT deployment experience with real-time inference optimization on embedded platforms (Jetson, Horizon, etc.)
  • CUDA programming fundamentals; ability to write or debug custom kernels
  • Proficient in C++ and Python with ROS / ROS2 development experience
  • Proficient with AI coding agents
Nice to Have
  • Engineering experience with 6DoF object pose estimation (FoundPose, FoundationPose, GDR-Net, etc.)
  • Familiarity with 3D Gaussian Splatting or NeRF for scene reconstruction or data augmentation
  • Experience with robot manipulation or teleoperation systems
  • End-to-end development experience with automated annotation pipelines or ground truth generation systems
  • Published research in perception, pose estimation, or robotics
What We Offer
  • Direct involvement in the most critical technical challenge in embodied intelligence: producing high-quality robot training data
  • An environment working alongside top-tier robotics engineers and ML researchers
  • Proprietary hardware platforms (humanoid robots, camera arrays, data gloves)
  • A fast-paced, high-autonomy 0โ†’1 work environment
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