FREE Japanese grammar • particles • polite style

Japanese Grammar Checker - Check Japanese Sentences Free

Japanese Grammar Checker

Paste Japanese text to review particles, verb endings, tense, polite and plain style, punctuation, and sentence flow. The checker is built for learners, emails, short messages, essays, and draft Japanese paragraphs that need a grammar-focused review.

Free Japanese grammar checks
Japanese Review

See a Japanese Grammar Check

私は昨日学校に行きます。

彼は日本語を勉強するです。

この文章は自然じゃありませんです。

明日、友達を会います。

私は昨日学校に行きました。

彼は日本語を勉強しています。

この文章は自然ではありません。

明日、友達に会います。

Particles, tense, verb forms, and politeness reviewed

Suggestions should be checked against the intended meaning

A Japanese Grammar Checker for Learners and Everyday Writing

Use this tool when Japanese word order looks close, but particles, verb endings, tense, or politeness make the sentence feel uncertain.

Check Japanese Particles

Review は, が, を, に, で, と, から, and other particles that change the meaning of a Japanese sentence.

Fix Verb Forms and Politeness

Compare plain, polite, past, negative, and te-form usage so the corrected sentence matches the situation.

Copy a Cleaner Draft

Paste a message, diary entry, essay paragraph, or study sentence, then review and copy a more natural version.

How It Works

Step 1

Paste Japanese Text

Use complete sentences when possible. Japanese grammar depends heavily on context, omitted subjects, and the relationship between speaker and reader.

Step 2

Keep Japanese Selected

This page opens with Japanese as the language setting and grammar as the check type, so particles and verb forms stay the focus.

Step 3

Review Meaning Before Copying

Check whether the correction preserves your intended subject, level of politeness, time, and nuance before using it.

Japanese Grammar Issues This Tool Reviews

A useful Japanese grammar checker should explain the type of mistake, not only rewrite the sentence.

Particles and Case Marking

友達に会います / ご飯を食べます

The checker reviews likely particle mismatches where the relationship between verb, object, place, and direction is unclear.

  • は vs が
  • を vs に
  • で vs に

Tense and Verb Endings

昨日行きました / 明日行きます

Japanese tense and aspect often depend on time words and context. The tool checks past, present, negative, and ongoing forms.

  • Past and non-past
  • Negative forms
  • ている usage

Polite and Plain Style

です・ます / だ・る forms

Mixed politeness can make writing sound inconsistent. Suggestions help align formal emails, study answers, and casual notes.

  • Polite style
  • Plain style
  • Honorific caution

Natural Sentence Flow

意味を変えずに自然にする

The page focuses on grammar and clarity while keeping your original meaning, names, and vocabulary choices whenever possible.

  • Word order
  • Missing context
  • Readable correction

Examples

A useful Japanese grammar checker should explain the type of mistake, not only rewrite the sentence.

Particle choice

Original: 明日、友達を会います。 Suggested: 明日、友達に会います。

Past tense

Original: 私は昨日学校に行きます。 Suggested: 私は昨日学校に行きました。

Polite style

Original: これは便利だと思いますです。 Suggested: これは便利だと思います。

Natural wording

Original: 日本語を勉強するです。 Suggested: 日本語を勉強しています。

What to Review Before You Accept a Japanese Correction

Japanese grammar suggestions can be useful, but context still matters. Use this table to decide what needs a quick manual check.

Input situation What gets checked Best next step
Learner sentence with a particle error Case particles, topic markers, direction, object marking, and likely verb relationship. Accept the fix when the meaning and relationship between words stay the same.
Message or email with mixed formality Polite endings, plain forms, sentence-final expressions, and tone consistency. Match the correction to the reader: teacher, customer, coworker, friend, or study partner.
Long paragraph with unclear subjects Sentence flow, repeated words, missing context, and tense consistency. Add context if the tool cannot know who did the action or what noun a phrase modifies.

Accuracy, Style, and Privacy Notes

Japanese grammar suggestions can be useful, but context still matters. Use this table to decide what needs a quick manual check.

Context can change the right answer

Japanese often omits subjects and objects. If the surrounding conversation changes the meaning, review the correction manually.

Honorific language needs judgment

Keigo, humble language, and customer-facing wording can be sensitive. Use suggestions as a draft, then confirm the tone.

Avoid sensitive text

Do not paste passwords, private IDs, confidential business text, legal details, medical records, or unpublished private documents into any online checker.

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FAQ

Is this Japanese grammar checker free?

Yes. You can paste Japanese text and check grammar for free without creating an account. Review suggestions before using them in a final message or assignment.

Can it check Japanese particles?

Yes. It can review likely particle issues such as は, が, を, に, で, と, and other common markers, but the best choice can depend on context.

Does it fix polite and plain Japanese?

It can help identify mixed politeness and suggest a more consistent style. Formal emails, keigo, and customer messages still need human review.

Can beginners use it for Japanese homework?

Yes. It is useful for checking study sentences and short paragraphs, but you should still learn why the correction works instead of copying blindly.

Can it check romaji?

The tool works best with Japanese text in kana and kanji. Romaji may be understood in some cases, but Japanese script gives stronger grammar context.

Will it rewrite my Japanese completely?

The page is designed for grammar correction, not a full creative rewrite. Suggestions should preserve the original meaning whenever possible.

Can I use it for essays or emails?

Yes. Paste a paragraph, email draft, or essay section. Check the tone, vocabulary, names, and intended meaning before sending or submitting.

Is Japanese grammar always one correct answer?

No. Topic choice, omitted subjects, formality, and nuance can create several acceptable versions. Treat the result as a proofreading draft.

Check Your Japanese Grammar Before You Send

Paste Japanese text above, review particles and verb forms, then copy the cleaner version.

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