Writing in English when it is not your first language involves two distinct challenges that are often conflated. The first is correctness: avoiding grammatical errors, spelling mistakes, and punctuation problems that native speakers would immediately notice. The second is fluency: producing text that does not just follow the rules but sounds natural, reads smoothly, and uses idiomatic expressions in the way a native speaker would. A sentence can be grammatically perfect and still sound unmistakably like it was written by someone thinking in another language.
Grammarly and DeepL Write address both challenges, but they approach them from fundamentally different starting points. Grammarly began as a grammar checker in 2009 and has evolved into a comprehensive writing assistant with over 30 million daily active users. DeepL Write emerged from DeepL, the translation company known for producing translations that read more naturally than those from Google Translate. Understanding these origins is essential to understanding which tool serves non-native speakers better.
Grammarly Overview
Grammarly was founded in 2009 by Alex Shevchenko and Max Lytvyn in Ukraine. The company is headquartered in San Francisco and was valued at approximately $13 billion in 2021. It is one of the world’s largest AI writing assistants, with over 30 million daily active users across its platforms.
What Grammarly Does for Non-Native Speakers
Grammar, Spelling, and Punctuation: Grammarly’s core function remains its strongest. The tool catches subject-verb agreement errors, incorrect tense usage, article misuse (a vs. the — one of the most persistent difficulties for non-native speakers), preposition errors, and dozens of other grammatical issues. For speakers of languages that do not use articles, do not distinguish between countable and uncountable nouns, or have different verb conjugation patterns, these corrections are immediately valuable.
Clarity and Conciseness: Non-native speakers often write sentences that are technically correct but unnecessarily complex — a tendency that comes from translating complex structures from their first language. Grammarly identifies wordy constructions, passive voice, and convoluted sentence structures, suggesting simpler alternatives.
Tone Detection: Grammarly analyzes the emotional tone of your writing and tells you how it is likely to be perceived: formal, casual, confident, friendly, concerned, diplomatic. For non-native speakers, who may not intuitively grasp the connotations of certain word choices in English, this feedback is valuable. The difference between “I suggest we reconsider” (diplomatic) and “We need to change this” (direct) can determine how a message is received, and non-native speakers do not always recognize which register they are using.
Full-Sentence Rewrites: When a sentence is not just grammatically incorrect but structurally awkward, Grammarly can suggest a complete rewrite. This goes beyond fixing individual errors to producing a sentence that flows naturally.
GrammarlyGO: The generative AI feature can draft text from prompts, rewrite paragraphs in a different tone, and help users compose emails and messages. For non-native speakers who struggle with the blank page, having an AI suggest a first draft that they can then modify is a significant productivity boost.
Plagiarism Detection (Premium): This feature is particularly relevant for international students writing academic papers in English, checking their work against a database of over 16 billion web pages.
Platform Coverage
Grammarly is available as browser extensions for Chrome, Edge, Firefox, and Safari; desktop applications for Windows and macOS; mobile keyboards for iOS and Android; and integrations with Microsoft Office and Google Docs. This means it works in virtually every text field where a non-native speaker might write in English — email, chat, documents, social media, and more.
Pricing
- Free: Basic grammar, spelling, and punctuation checking
- Premium: Approximately $12 per month — adds tone detection, clarity suggestions, full-sentence rewrites, plagiarism detection, and GrammarlyGO with higher usage limits
- Business: Approximately $15 per user per month — adds team management, style guides, brand tone guidelines, and analytics
- Enterprise: Custom pricing with SSO, SCIM, and advanced security
Languages
Grammarly primarily supports English, with limited support for German, French, Spanish, and Portuguese. The depth of analysis in English is significantly greater than in any other language.
DeepL Write Overview
DeepL Write was introduced in late 2022 by DeepL SE, the Cologne-based company behind DeepL Translator. DeepL Translator had already established a reputation for producing translations that sound more natural and idiomatic than those from competing services, particularly for European language pairs. DeepL Write applies the same underlying technology — transformer models trained on vast multilingual corpora — to the task of improving text within a single language.
What DeepL Write Does for Non-Native Speakers
Whole-Text Rewriting: Where Grammarly identifies specific errors and suggests fixes for each one, DeepL Write takes a different approach. You paste text into the interface, and it produces a revised version that improves the entire text simultaneously — correcting errors, improving word choice, and making the prose sound more natural. The experience is closer to having a bilingual editor review your draft than to receiving a list of corrections.
Fluency Over Correctness: DeepL Write’s greatest strength for non-native speakers is its ability to make text sound idiomatic. The tool catches not just grammar errors but the kind of awkward phrasing, unnatural word combinations, and register mismatches that mark text as non-native. A sentence that is “correct” but reads like a literal translation from German, Spanish, or Japanese gets rewritten to sound like it was originally composed in English.
Word Choice Alternatives: For each rewritten passage, DeepL Write highlights words and phrases where it has made changes and offers alternative suggestions. You can click on highlighted words to see other options, giving you control over the final version.
Tone and Style Adjustments: DeepL Write allows you to adjust the formality level of the output — making text more formal or more casual. For business communication, where the appropriate register varies by context, this is useful.
Multilingual Depth: DeepL Write supports English, German, French, Spanish, Portuguese, and Italian. While this is fewer languages than Grammarly’s English-centric approach might suggest as a disadvantage, the quality of DeepL Write’s support in each of these six languages is deep and consistent.
Platform Coverage
DeepL Write is accessible through the DeepL web interface and DeepL desktop applications for Windows and macOS. It integrates with some platforms, but its browser extension is not as comprehensive as Grammarly’s. DeepL Write does not yet offer the seamless, works-everywhere integration that makes Grammarly feel invisible.
Pricing
DeepL Write is available in the free tier of DeepL with usage limitations. Full access is included with DeepL Pro plans, which start at approximately $8.74 per month for individuals and scale up for team and enterprise plans.
Languages
English, German, French, Spanish, Portuguese, and Italian.
Comparison: Where Each Tool Excels
Grammar Error Detection
Grammarly is stronger. Grammarly has spent over 15 years building its grammar engine. It catches a wider range of errors with greater specificity, provides explanations for why something is wrong, and handles edge cases that confuse simpler tools. For non-native speakers who want to understand their mistakes — not just have them fixed — Grammarly’s explanations are educational.
DeepL Write corrects grammar as part of its rewriting process, but it does not flag individual errors or explain why changes were made. If you want to learn from your mistakes, Grammarly is the better teacher.
Fluency and Naturalness
DeepL Write is stronger. This is the area where DeepL’s translation heritage pays dividends. DeepL Write does not just fix what is wrong; it makes what is “right but awkward” sound natural. For non-native speakers, the gap between correct English and natural English is often the most frustrating part of writing, and DeepL Write addresses it more effectively than Grammarly.
Grammarly’s clarity and conciseness suggestions help with naturalness, but the tool is fundamentally correction-oriented. It assumes that what you wrote is the starting point and suggests adjustments. DeepL Write is more willing to rethink the entire sentence.
Tone and Register
Grammarly offers more detail. Grammarly’s tone detection identifies multiple dimensions of tone simultaneously and provides specific feedback. DeepL Write offers a formality slider but does not provide the granular tone analysis that Grammarly does.
For non-native speakers who need to navigate the nuances of English-language business communication — knowing when “I would appreciate your feedback” is more appropriate than “Please give me feedback” — Grammarly’s tone detection is more informative.
Integration and Convenience
Grammarly wins decisively. Grammarly works in Gmail, Slack, Google Docs, Microsoft Word, social media platforms, and virtually any text field in any browser. DeepL Write requires you to visit the DeepL website or use the desktop app and paste text in. For everyday writing where you want assistance without interrupting your workflow, Grammarly’s seamless integration is a significant advantage.
Learning and Skill Development
Grammarly is better for learning. Because Grammarly shows you each error, explains the rule behind it, and lets you accept or reject individual suggestions, it functions as a writing tutor. Over time, you start recognizing patterns — “I always misuse ‘which’ and ‘that’” or “I keep using passive voice” — and your unassisted writing improves.
DeepL Write produces a polished output but does not teach you why changes were made. It is an efficient tool for producing good writing, but a less effective tool for becoming a good writer.
Pricing Comparison
For an individual user:
- Grammarly Premium: ~$12/month
- DeepL Pro (including Write): ~$8.74/month
DeepL is cheaper and includes both translation and writing assistance. Grammarly costs more but offers broader platform coverage and a wider range of writing features including plagiarism detection.
Verdict
Choose Grammarly if:
- You want comprehensive grammar error detection with explanations that help you learn
- You need a tool that works seamlessly everywhere you write, without copy-pasting
- Tone detection and brand tone guidelines matter for your work
- You want plagiarism detection for academic or professional content
- Your primary language is English, and you want the deepest possible English-language support
Choose DeepL Write if:
- Your biggest challenge is fluency and naturalness, not grammar correctness
- You write in multiple European languages and want consistent quality across all of them
- You prefer a whole-text rewriting approach over individual error correction
- You also use DeepL Translator and want a unified platform for translation and writing
- Budget is a significant factor and you want good value from a single subscription
Consider using both if:
- You write first drafts that need fluency improvement (use DeepL Write to rewrite) and then final review for grammar, tone, and plagiarism (use Grammarly to polish)
- This two-step workflow is particularly effective for high-stakes documents — business proposals, academic papers, published content — where both naturalness and correctness are non-negotiable
The honest answer is that neither tool alone perfectly serves non-native English speakers. Grammarly catches more errors but occasionally misses the deeper fluency issues. DeepL Write produces more natural-sounding text but does not teach you why your original was awkward. The ideal workflow often involves both, and the combined cost — roughly $20 per month — is modest compared to the value of consistently producing English text that sounds professional, natural, and correct.
References
- Grammarly. “About Grammarly.” Grammarly Official Website. https://www.grammarly.com
- Wikipedia contributors. “Grammarly.” Wikipedia, The Free Encyclopedia. https://en.wikipedia.org/wiki/Grammarly
- Grammarly. “Plans and Pricing.” Grammarly Official Website. https://www.grammarly.com/plans