Best Portuguese Grammar Checkers in 2026

Brazilian vs European Portuguese

Before picking a grammar checker, you need to understand why this distinction matters. Brazilian Portuguese (PT-BR) and European Portuguese (PT-PT) aren't just accent differences — they have real grammatical divergences that affect what counts as "correct."

• Tu vs. você — In Brazil, "você" is standard for "you" and takes third-person verb conjugations. In Portugal, "tu" is common and requires second-person forms. A checker that flags "tu falas" as wrong is applying Brazilian rules to European text.
• Gerund vs. infinitive — Brazilians say "estou fazendo" (I am doing). The Portuguese say "estou a fazer." Both are correct in their respective variants, but a grammar checker needs to know which one you're writing in.
• Spelling reform (Acordo Ortográfico) — The 2009 spelling reform unified some spelling between variants, dropping silent consonants in European Portuguese (e.g., "acção" became "ação"). But adoption is uneven — Portugal accepted it officially, yet many writers still use pre-reform spelling. A good checker should handle both.
• Pronoun placement — Brazilian Portuguese tends to place object pronouns before the verb ("me diga"), while European Portuguese places them after ("diga-me"). This is a common source of false corrections.

Any grammar checker worth using for Portuguese must let you select your variant. If it doesn't, expect a flood of false positives.

Best Portuguese Grammar Checkers

1. LanguageTool — Best Overall for Portuguese

LanguageTool has dedicated rule sets for both PT-BR and PT-PT, making it the most reliable free option. You select your variant in settings and the tool applies the correct grammar, spelling, and style rules accordingly.

• Portuguese accuracy: Excellent — catches verb conjugation errors, pronoun placement issues, Acordo Ortográfico spelling, and accent marks
• Variants: Separate modes for Brazilian and European Portuguese
• How it works: Browser extension, web editor, LibreOffice/Word add-on
• Price: Free (limited checks) or €5/month for premium

Limitation: Works well in browsers, but there's no true system-wide integration on macOS. You can't use it natively in Mail or Notes.

2. Flip — Best Portuguese-Specific Tool

Flip (also known as FLiP by Priberam) is a Portuguese-first tool built by Priberam, the company behind Portugal's leading dictionary. It's designed exclusively for Portuguese and understands the language at a depth most international tools can't match.

• Portuguese accuracy: Very strong — deep knowledge of both variants, excellent dictionary coverage
• Variants: Supports PT-BR and PT-PT with pre- and post-reform spelling
• How it works: Web editor, desktop app (Windows/Mac), browser extension
• Price: Free web version with limits, paid plans from €2/month

Limitation: Portuguese-only — no English or other languages. Less useful for multilingual writers.

3. FlowWrite — Best for Mac Users

FlowWrite is a macOS menu bar app that checks grammar in every application. Select text, press Tab, and the AI corrects your Portuguese in place — whether you're in Mail, Slack, VS Code, or any other app.

• Portuguese accuracy: Very good — AI-powered correction handles conjugation, accents, and pronoun placement for both variants
• How it works: System-wide on macOS. Works in every app with text input.
• Price: Free (10 corrections/day) or $2.99/month for 1,000 corrections/day
• Multilingual: Handles Portuguese and English seamlessly — ideal for Portuguese speakers writing in both languages

Limitation: macOS only. No Windows or web version. Requires the Accessibility permission.

4. Microsoft Editor — Best for Word and Outlook Users

Microsoft Editor has solid Portuguese support baked into Word, Outlook, and the Edge browser. It handles both PT-BR and PT-PT and benefits from Microsoft's decades of spellcheck data.

• Portuguese accuracy: Good — reliable spelling and basic grammar, weaker on style and complex sentence structures
• Variants: Supports both Brazilian and European Portuguese
• How it works: Built into Microsoft 365, Edge extension
• Price: Free with Microsoft account, premium features with Microsoft 365 ($7/month)

Limitation: Locked to the Microsoft ecosystem. Grammar corrections outside of Word and Outlook are basic.

5. Grammarly — No Portuguese Support

Grammarly is the most popular grammar checker globally, but it does not support Portuguese at all. If you write exclusively in Portuguese, Grammarly won't help you. It's included here because many people search for it — save yourself the installation.

• Portuguese accuracy: None — Portuguese is not a supported language
• English accuracy: Excellent — if you also write in English, Grammarly is top-tier for that
• Price: Free (basic) or $12/month (premium)

Comparison Table

For Portuguese-English Writers

Many Portuguese speakers write in both Portuguese and English daily — whether for work, study, or communicating with international teams. The challenge is that most tools are built for one language or the other, not both.

LanguageTool handles both languages well, but you need to switch your language setting manually or rely on auto-detection, which sometimes guesses wrong on short texts. Flip is excellent for Portuguese but won't help with your English emails.

FlowWrite is designed for exactly this use case. The AI detects your language automatically and applies the right corrections — no mode switching. Write a Portuguese message in WhatsApp, correct it with one keystroke. Switch to an English reply in Slack — same keystroke, same tool. For bilingual writers on macOS, it's the simplest workflow.