# AI tools for “Annotation tool”

407 matching tools; showing 24, ranked by relevance.

| # | Tool Name | Monthly Visits | MoM Growth Rate | Pricing Model | Summary | Why it matched | Profile (Markdown) |
| :--- | :--- | :--- | :--- | :--- | :--- | :--- | :--- |
| 1 | [SyncSketch](https://openaitools.app/tool/syncsketch) | 1,284,451 | +17.3% | Free Trial, Paid | Frame-accurate video, 3D and image review that keeps creative teams in sync from one link. | keywords 100%; semantic match | [.md](https://openaitools.app/tool/syncsketch.md) |
| 2 | [SuperAnnotate](https://openaitools.app/tool/super-annotate) | 386,034 | +37.4% | Free Trial, Contact for Pricing | AI data infrastructure for building production-grade models | keywords 100%; semantic match | [.md](https://openaitools.app/tool/super-annotate.md) |
| 3 | [OpenTrain AI](https://openaitools.app/tool/opentrain-ai) | 1,469,348 | +11.2% | Contact for Pricing | Hire tested AI trainers and data labelers for RLHF, evaluation, and annotation | keywords 100%; semantic match | [.md](https://openaitools.app/tool/opentrain-ai.md) |
| 4 | [Goodnotes](https://openaitools.app/tool/goodnotes) | 3,227,341 | +10.8% | Freemium, Free Trial | Handwritten notes, PDF markup, and AI study tools on one canvas | keywords 100%; semantic match | [.md](https://openaitools.app/tool/goodnotes.md) |
| 5 | [Appen](https://openaitools.app/tool/appen-com) | 665,840 | +0.2% | Contact for Pricing | Human-validated training data and evaluation services for frontier AI models | keywords 100%; semantic match | [.md](https://openaitools.app/tool/appen-com.md) |
| 6 | [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 | keywords 100%; semantic match | [.md](https://openaitools.app/tool/encord-com.md) |
| 7 | [Label Studio](https://openaitools.app/tool/label-studio) | 137,199 | -16.1% | Contact for Pricing, Free | Label any data. Evaluate any AI. | keywords 100%; semantic match | [.md](https://openaitools.app/tool/label-studio.md) |
| 8 | [BasicAI Cloud](https://openaitools.app/tool/basicai-cloud) | 21,670 | -13.1% | Freemium, Enterprise Quote | AI data annotation platform and managed labeling services for AI training data | keywords 100%; semantic match | [.md](https://openaitools.app/tool/basicai-cloud.md) |
| 9 | [KROCK.IO](https://openaitools.app/tool/krock-io) | 133,777 | +9.9% | Freemium, Free Trial, Paid | Frame-accurate video review and approval for creative teams | keywords 100%; semantic match | [.md](https://openaitools.app/tool/krock-io.md) |
| 10 | [Innovatiana](https://openaitools.app/tool/innovatiana) | 45,756 | +14.9% | Contact for Pricing | Innovatiana provides managed human data operations for AI — expert data labeling, annotation, RLHF and content moderation delivered by in-house trained specialists across computer vision, NLP, generative AI, audio and mu | keywords 100%; semantic match | [.md](https://openaitools.app/tool/innovatiana.md) |
| 11 | [clickworker](https://openaitools.app/tool/clickworker-com) | 1,861,149 | +0.5% | Contact for Pricing | Crowdsourcing data services for AI training and market data | keywords 100% | [.md](https://openaitools.app/tool/clickworker-com.md) |
| 12 | [Labelbox](https://openaitools.app/tool/labelbox) | 762,803 | -22.8% | Contact for Pricing | The environments frontier AI trains on, and the agents that do the recurring work | keywords 100%; semantic match | [.md](https://openaitools.app/tool/labelbox.md) |
| 13 | [Roboflow](https://openaitools.app/tool/roboflow) | 1,431,204 | +6.6% | Freemium, Contact for Pricing | Build, train, and deploy computer vision for the physical world | keywords 100% | [.md](https://openaitools.app/tool/roboflow.md) |
| 14 | [DataVLab](https://openaitools.app/tool/datavlab) | 12,740 | -7.8% | Contact for Pricing | ISO 27001 data annotation services for AI and ML teams in regulated industries | keywords 100%; semantic match | [.md](https://openaitools.app/tool/datavlab.md) |
| 15 | [Grammarly](https://openaitools.app/tool/grammarly) | 58,867,412 | -1.5% | Freemium | Cross-platform AI writing assistant delivering real-time grammar correction, tone alignment, authorship tracking, and team style guides. | semantic match | [.md](https://openaitools.app/tool/grammarly.md) |
| 16 | [Flexnote](https://openaitools.app/tool/flexnote) | 41,017 | +113.1% | Freemium | Local-first visual note-taking on an infinite canvas with mind maps and knowledge-base AI | keywords 100%; semantic match | [.md](https://openaitools.app/tool/flexnote.md) |
| 17 | [Unitlab](https://openaitools.app/tool/unitlab-ai) | 3,903 | -36.4% | Freemium, Contact for Pricing | Curate, annotate and QA multimodal training data in one governed workspace | keywords 100%; semantic match | [.md](https://openaitools.app/tool/unitlab-ai.md) |
| 18 | [LightPDF](https://openaitools.app/tool/lightpdf-com) | 1,742,568 | -15.3% | Freemium | Free AI-powered PDF editor, converter and reader for every device | keywords 100% | [.md](https://openaitools.app/tool/lightpdf-com.md) |
| 19 | [T-Rex Label](https://openaitools.app/tool/t-rex-label) | 9,900 | +37.6% | Free | Browser-based AI data labeling that turns one box into a whole annotated dataset | keywords 100%; semantic match | [.md](https://openaitools.app/tool/t-rex-label.md) |
| 20 | [LanguageTool](https://openaitools.app/tool/languagetool) | 5,707,795 | -4.2% | Freemium | AI grammar, spelling and style checker for 30+ languages | semantic match | [.md](https://openaitools.app/tool/languagetool.md) |
| 21 | [UPDF AI](https://openaitools.app/tool/updf-ai) | 1,050,387 | -7.2% | Freemium, Free Trial, Paid | Cross-platform PDF editing with GPT-powered AI for reading, translating, and signing documents | keywords 100% | [.md](https://openaitools.app/tool/updf-ai.md) |
| 22 | [PDNob PDF Editor](https://openaitools.app/tool/pdnob-pdf-editor) | 2,376,518 | +1.2% | Freemium, Free Trial, Paid | AI-powered PDF editor for Windows, Mac and iOS | keywords 100%; semantic match | [.md](https://openaitools.app/tool/pdnob-pdf-editor.md) |
| 23 | [Defined.ai](https://openaitools.app/tool/definedcrowd-com) | 146,251 | -21% | Contact for Pricing | Enterprise AI training data, annotation and evaluation services | keywords 100% | [.md](https://openaitools.app/tool/definedcrowd-com.md) |
| 24 | [Resume Worded](https://openaitools.app/tool/resume-worded) | 929,140 | -23.6% | Freemium | Instant AI feedback on your resume and LinkedIn profile | keywords 100% | [.md](https://openaitools.app/tool/resume-worded.md) |

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