
SpecialistOpenAI's flagship multimodal assistant powered by GPT-6 and GPT-5.6 for reasoning, coding, and deep research.
SpecialistOpenAI's flagship multimodal assistant powered by GPT-6 and GPT-5.6 for reasoning, coding, and deep research.
Grammarly records 58,867,412 monthly visits with -1.5% month-over-month growth and Freemium pricing. LightPDF records 1,742,568 monthly visits with -15.3% growth and Freemium pricing.

Free AI-powered PDF editor, converter and reader for every device
| Dimension / Metric | ![]() | ![]() |
|---|---|---|
| Official Domain | grammarly.com | lightpdf.com |
| Pricing Model | Freemium | Freemium |
| Monthly Visits | 58.87M (58,867,412) | 1.74M (1,742,568) |
| MoM Traffic Delta | -916.08K (-1.5%) | -314.58K (-15.3%) |
| Primary Market & Share | 🇺🇸 United States (51.9%) | 🇮🇳 India (24.9%) |
| Direct Visits / mo | 25.4M | 442.07K |
| User Rating | 4.4 | 4.2 |
| Supported Platforms | Website | Website |

Cross-platform AI writing assistant delivering real-time grammar correction, tone alignment, authorship tracking, and team style guides.
Works natively inside Chrome, Safari, Firefox, Edge, Windows, Mac, Google Docs, MS Office, and mobile keyboards to flag grammar mistakes, rewrite tangled sentences, and shift tone toward confident, empathetic, or executive registers.
Deploys contextual AI agents that predict how a target audience will react to a draft, locate credible supporting citations, grade essays against rubric criteria, and generate drafts using up to 2,000 monthly prompts on Pro.
Scans text against billions of web pages and academic databases for accidental plagiarism, detects AI-generated passages, and logs transparent document provenance via Authorship reports in Google Docs and Word.
Enables teams on Pro and Enterprise plans to codify company terminology, ban deprecated jargon, enforce inclusive language, insert shared Snippets, and surface internal company definitions inline.

Free AI-powered PDF editor, converter and reader for every device
Upload a PDF and ask questions in natural language, follow up on details and see which passages the answers came from. A separate chat mode works with YouTube videos.
Translate whole documents, including scanned and image-based PDFs, into 20+ languages while keeping the original formatting and layout intact.
Convert invoices, receipts, bank statements and purchase orders into structured, editable Excel files automatically.
Edit text and images, OCR scanned pages, convert to and from Office formats, then merge, split, compress, watermark, sign and annotate.

SpecialistOpenAI's flagship multimodal assistant powered by GPT-6 and GPT-5.6 for reasoning, coding, and deep research.
SpecialistOpenAI's flagship multimodal assistant powered by GPT-6 and GPT-5.6 for reasoning, coding, and deep research.
SpecialistAnthropic's frontier AI workspace powered by Claude 5.5 for agentic coding, analysis, and nuanced writing.
SpecialistAnthropic's frontier AI workspace powered by Claude 5.5 for agentic coding, analysis, and nuanced writing.

SpecialistEnterprise-grade neural machine translation, AI writing refinement, and real-time voice translation across thirty-plus global languages.
SpecialistEnterprise-grade neural machine translation, AI writing refinement, and real-time voice translation across thirty-plus global languages.
Excels at heavy paraphrasing and text rewriting, but offers less seamless inline real-time proofreading across all apps.
Excels at heavy paraphrasing and text rewriting, but offers less seamless inline real-time proofreading across all apps.

Provides strong multilingual grammar and style checking across apps, but offers fewer advanced generative AI features.
Provides strong multilingual grammar and style checking across apps, but offers fewer advanced generative AI features.
Offers a completely free PDF editing and AI assistant experience, but lacks some of LightPDF's cloud-native collaboration features.
Offers a robust desktop suite for OCR and editing, but requires software installation unlike cloud platforms.
Offers a robust desktop suite for OCR and editing, but requires software installation unlike cloud platforms.

Delivers deeper manuscript analysis and structural reports, but has a steeper learning curve than Grammarly.
Delivers deeper manuscript analysis and structural reports, but has a steeper learning curve than Grammarly.

Provides quick browser-based PDF editing and e-signatures, but has a less advanced conversational AI assistant.
Provides quick browser-based PDF editing and e-signatures, but has a less advanced conversational AI assistant.
SpecialistAI academic writing assistant that edits, cites, and checks your manuscript right where you write
SpecialistAI academic writing assistant that edits, cites, and checks your manuscript right where you write

Provides a more polished cross-platform desktop PDF editing suite, but requires a paid upgrade for full AI features.
Offers a streamlined conversational interface for querying PDFs, but provides fewer document editing and conversion utilities.