Hire the Best Ontologists

Clients rate our Ontologists
Rating is 4.8 out of 5.
4.8/5
Based on 101 client reviews
Parwiz B.

Fulwood, United Kingdom

$20/hr
5.0
35 jobs

Stop Wasting Millions on AI Models Crippled by Bad Data. Your AI model is only as powerful as its training data. Inconsistent data annotations sabotage performance, costing you weeks and millions in lost ROI. If your team is cleaning Machine Learning datasets instead of building, you need a better solution. As a Top Rated Plus expert, I deliver Training Ready Intelligence. My mission: transform your raw training data into high fidelity, structured assets for peak AI model performance in Computer Vision, NLP, and Machine Learning. I specialize in clean, reliable data annotation for images, video, and text. I ensure data quality directly impacts your model accuracy and bottom line. I've managed massive data labeling projects, consistently exceeding expectations. Why elite AI teams choose me: Guaranteed Accuracy: 100% pipeline ready data annotation, every time. No re work, no debugging. Zero Management Overhead: You define; I execute with precision and autonomy. Focus on AI development, not data prep. Accelerated ROI: Cut training cycles, deploy faster. Transform raw data into a competitive advantage. My Core Expertise: Image Annotation: Bounding Box, Polygon, Semantic Segmentation, Keypoint (Computer Vision) Video Annotation: Object Tracking, Event Detection (Computer Vision) Text Annotation: NER, Sentiment Analysis, Classification (NLP) Data Labeling & Dataset Preparation Ready to elevate your AI project? Click Message. Let's build the robust training data foundation your AI models deserve. Stop settling for "good enough" data annotation; get it right the first time. Best Regards, Parwiz

  • Data Annotation
  • Data Labeling
  • Video Annotation
  • Image Annotation
  • Machine Learning Model
  • n8n
  • LLM Prompt
  • Project Management
  • SuperAnnotate
  • Roboflow
  • CVAT
  • Automation
  • Make.com
  • LLM Prompt Engineering
  • Computer Vision
  • Data Quality Assessment
  • Image Segmentation
  • Object Detection
  • Object Detection & Tracking
  • Deep Learning
Shikenah C.

Legaspi, Philippines

$10/hr
4.0
22 jobs

Hi! I'm Shikenah, a detail-oriented freelancer specializing in ⦿ Data Annotation ⦿ Quality Assurance ⦿ Virtual Assistance ⦿ Data Management ⦿ AI Prompter ⦿ AI Generation ⦿ Video Editing I enjoy helping businesses build accurate AI datasets, organize information, and complete projects efficiently with a strong focus on quality and consistency. 😎 What I Can Do ✅ • AI Data Annotation & Labeling • Semantic & Instance Segmentation • Image & Video Annotation • Bounding Box, Polygon & Keypoint Annotation • Object Detection & Image Classification • Data Validation & Quality Assurance (QA) • AI Model Training Support • Satellite & Aerial Image Annotation • Solar Rooftop Annotation • Content Moderation • Data Entry & Web Research • Metadata Management • Microsoft Excel & Google Sheets • Virtual Assistance & Administrative Support • File Organization & Documentation Tools & Software • CVAT • Label Studio • Supervisely • LabelMe • Microsoft Excel • Google Sheets • Google Workspace • Adobe Premiere Pro • Adobe After Effects • Adobe Photoshop • Adobe Lightroom • CapCut • Canva Why Work With Me? ✔ Detail-oriented and highly accurate ✔ Fast learner who adapts quickly to new guidelines ✔ Strong quality control and problem-solving skills ✔ Reliable, organized, and deadline-driven ✔ Excellent communication and responsiveness ✔ Able to work independently with minimal supervision ✔ Committed to delivering consistent, high-quality results I believe great work comes from accuracy, reliability, and clear communication. Whether you need AI data annotation, quality checking, administrative support, or data management, I'm committed to delivering results you can trust. Let's work together to make your project a success!

  • Data Annotation
  • Data Labeling
  • Data Analysis
  • Data Segmentation
  • Image Segmentation
  • Data Science
  • Quality Assurance
  • Image Annotation
  • Data Management
  • AI Model Training
  • Video Annotation
  • Administrative Support
  • Artificial Intelligence
  • AI Chatbot
  • AI Development
  • Content Moderation
  • Computer Vision
  • AI Content Editing
  • Real Estate
  • Prompt Engineering
Mazhar U.

Peshawar, Pakistan

$9/hr
5.0
22 jobs

Imagine spending thousands of dollars training an AI model—only to realize the labels were flawed. That’s where I come in. I’m 𝗠𝗮𝘇𝗵𝗮𝗿 𝗨𝗱 𝗗𝗶𝗻, the founder of 𝗔𝗡𝗡𝗢𝗣𝗘𝗧𝗧, a data annotation and AI development agency trusted by AI startups and enterprises worldwide. With 4+ years of experience and a team of 178+ skilled annotators, I’ve personally led projects that helped train over 100 production-grade AI models—from medical image segmentation, agriculture dataset annotations, AI-based electric poles condition monitoring system to autonomous vehicle perception systems. 🌐𝗪𝗵𝘆 𝗖𝗹𝗶𝗲𝗻𝘁𝘀 𝗧𝗿𝘂𝘀𝘁 𝗠𝗲: 𝗣𝗿𝗲𝗰𝗶𝘀𝗶𝗼𝗻-𝗟𝗲𝘃𝗲𝗹 𝗦𝗲𝗴𝗺𝗲𝗻𝘁𝗮𝘁𝗶𝗼𝗻: I specialize in polygonal, pixel-wise, and semantic segmentation with an obsessive attention to detail. 𝗔𝗜-𝗔𝘄𝗮𝗿𝗲 𝗔𝗻𝗻𝗼𝘁𝗮𝘁𝗶𝗼𝗻: Unlike generic labelers, I understand the AI pipeline. I don’t just label—I label for performance. Every dataset is annotated with model training, accuracy, and edge-case handling in mind. 𝗘𝗻𝘁𝗲𝗿𝗽𝗿𝗶𝘀𝗲-𝗦𝗰𝗮𝗹𝗲 𝗢𝗽𝗲𝗿𝗮𝘁𝗶𝗼𝗻𝘀: Delivered $500,000+ worth of labeled data to top AI companies (like Moonvalley, SaharLabs etc) with proven systems for scalability, security, and deadlines. 𝗖𝘂𝘀𝘁𝗼𝗺 𝗧𝗼𝗼𝗹𝘀, 𝗥𝗲𝗮𝗹 𝗜𝗻𝘁𝗲𝗴𝗿𝗮𝘁𝗶𝗼𝗻: Worked across CVAT, Labelbox, SuperAnnotate, Roboflow, and even client-specific proprietary tools. 🌐𝗦𝘁𝗼𝗿𝘆 𝗼𝗳 𝗚𝗿𝗼𝘄𝘁𝗵: What began as a solo freelancing gig on Fiverr has now become a global agency delivering AI-ready data for some of the most innovative companies on Earth. Now offering our services on Upwork as well. 🛠️𝗦𝗲𝗿𝘃𝗶𝗰𝗲𝘀 𝗜 𝗢𝗳𝗳𝗲𝗿: ✦ Image & Video Segmentation (polygon, semantic, instance-based) ✦ Bounding Box, Keypoint & Landmark Annotation ✦ Text & Audio Annotation (multilingual available) ✦ Dataset Cleaning, Structuring & Preprocessing ✦ Consultancy on AI Dataset Design and Labeling Strategies ✦ AI Model Training and development Image annotation, Bounding boxes, 3D boxes, Video annotation, instance and semantic, Object labeling/tagging,Segmentation, Polygons masks, Text annotation, Line annotation, Key Points annotation, Cuboids, Image classification and categorization.

  • Video Annotation
  • Data Annotation
  • Image Annotation
  • Image Segmentation
  • CVAT
  • Data Labeling
  • Computer Vision
  • Data Entry
  • Data Collection
  • Roboflow
  • LabelMe
  • LabelImg
  • Labelbox
  • Computer Vision Software
  • SuperAnnotate
Luis Miguel A.

Murcia, Spain

$20/hr
5.0
8 jobs

I am an AI data trainer and evaluator with hands-on experience working on real-world large language model (LLM) projects. I specialize in reviewing, analyzing, and improving AI-generated content to ensure it meets high-quality standards. I have worked on AI training platforms such as Outlier AI and Invisible Technologies, where I contributed to the development and refinement of language models by evaluating responses, identifying errors, and applying detailed quality guidelines. What I do best: Evaluate and rank AI-generated responses based on accuracy, relevance, and coherence. Improve and optimize prompts and outputs for better model performance. Perform data annotation and labeling for AI training. Detect inconsistencies, biases, and errors in AI-generated content. Apply structured guidelines to ensure consistent and reliable results. Why work with me: Strong attention to detail and analytical thinking. Ability to follow complex instructions and maintain consistency. Experience working with real AI training workflows. Reliable, professional, and committed to high-quality results. I am passionate about improving AI systems and helping clients get the most accurate and effective outputs from their models.

  • Artificial Intelligence
  • Machine Learning Model
  • Natural Language Processing
  • Large Language Model
  • Prompt Engineering
  • AI Model Training
  • Data Annotation
  • Data Labeling
  • Data Analysis
  • Quality Assurance
  • Content Editing
  • Proofreading
  • Text Analysis
  • English
  • Spanish
Ayotunde O.

Ibadan, Nigeria

$30/hr
4.5
33 jobs

Licensed Medical Doctor + Top Rated AI Engineer (100% JSS, $30K+ earned on Upwork). I build LLM agents, RAG systems, and healthcare automations that ship. Most AI freelancers can write code. Very few can sit in a clinical handover, read a messy guideline PDF, or map a patient-intake workflow — and then build the system that automates it. That's the gap I fill: a practicing physician with 5 years on Upwork delivering data and AI projects for US and UK clients. WHAT I BUILD - LLM agents & multi-agent systems — LangGraph, Google ADK, OpenAI/Anthropic/Gemini APIs - RAG & document Q&A — LlamaIndex, ChromaDB, with PHI redaction (Microsoft Presidio) for sensitive data - AI voice agents — appointment booking, intake, lead qualification - Workflow automation — n8n, Make, Zapier + custom Python/FastAPI glue - Medical imaging AI — PyTorch fine-tuning of vision foundation models (LoRA/PEFT) - Data analytics & dashboards — Python, SQL, Tableau, Excel (where I started; still sharp) WHY THE "MD" MATTERS TO YOUR PROJECT - Healthcare builds: I understand clinical context, terminology, and PHI handling by training — compliant-by-design, not patched later. - Any build: medicine trains you to work under pressure with zero tolerance for sloppy errors. I check my work the way I check a drug dose. - Research rigor: first-author research on TB detection from chest X-rays using parameter-efficient fine-tuning of vision foundation models [FILL: "accepted at" or "under review at" MICCAI 2026 workshop — state it accurately]. RECENT WORK - Multi-agent clinical decision support assistant (Google ADK + Gemini) — [FILL: 1-line outcome] - PHI-safe RAG Q&A over clinical guidelines — [FILL: 1-line outcome] - Massive-scale computer-vision data annotation for Adobe — [FILL: 1-line outcome, e.g. volume/accuracy] HOW I WORK - Working prototype early — usually within the first week, so you see progress, not promises - Clear milestones, async updates, full documentation + handover video at the end - 4+ hours of daily overlap with US/UK time zones; average response under 4 hours - If your project isn't a fit, I'll tell you on day zero and point you in the right direction Message me with what you're trying to build or automate. I'll reply with whether I can help, how I'd approach it, and a realistic estimate — no fluff.

  • Data Extraction
  • Tableau
  • Data Scraping
  • Data Analytics & Visualization Software
  • Microsoft Excel
  • Data Visualization
  • Data Science
  • Data Processing
  • Dashboard
  • Data Analytics
  • Data Cleaning
  • Python
  • Machine Learning
  • AI Model Integration
  • LLM Prompt Engineering
  • Computer Vision
  • Medical Imaging
  • PyTorch
  • AI Agent Development
  • Healthcare
Harvey B.

Santa Rosa, Philippines

$5/hr
5.0
7 jobs

I specialize in image annotation and data labeling for AI and machine learning projects, with hands-on experience using tools such as CVAT, Roboflow, and LabelImg. I am skilled in bounding boxes, polygons, segmentation, image classification, dataset review, and accurate annotation based on project guidelines. I focus on delivering high-quality, consistent, and detail-oriented annotations to help improve AI model performance and training datasets. I am comfortable working with repetitive and precision-based tasks while maintaining accuracy and efficiency throughout the project. I am reliable, responsive to feedback, and committed to clear communication and on-time delivery. I welcome test tasks, trial projects, and long-term opportunities where I can contribute dependable annotation support and quality results.

  • Image Annotation
  • CVAT
  • Image Classification
  • LabelImg
  • Data Entry
  • Roboflow
  • Virtual Assistance
  • Copywriting

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Rates charged by Ontologists on Upwork can vary with a number of factors including experience, location, and market conditions. See hourly rates for in-demand skills on Upwork.

Why hire a Ontologist on Upwork?

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