Yes — completely free. No account, no ads, no tracking. Every feature is available immediately.

Does my document get uploaded to a server?

No. All .docx parsing and format comparison runs in your browser's JavaScript runtime — your file never leaves your device. We don't log requests, don't run analytics on tool inputs, and don't store any check history.

Which Word file formats are supported?

Only .docx (Office Open XML) is supported. Legacy .doc and macro-enabled .docm files are not. If your file is .doc, save it as .docx in Word first.

Which formatting properties can it detect?

DocxShuttle checks 6 categories: font (CJK + Latin), font size, line height, paragraph (first-line indent, space before/after), alignment, and page margins (top/bottom/left/right). Each of the 20 paragraph roles (title, body, abstract, etc.) can have independent rules.

Is there a file size limit?

There is no hard file size limit — processing capacity depends on your browser's available memory. In practice, .docx files under 50 pages typically parse in 2-3 seconds. If the UI slows with very large files, close other browser tabs.

How accurate is the check? Can it miss issues?

DocxShuttle parses .docx files based on the OOXML standard and accurately extracts paragraph-level style properties. However, Word's style inheritance chain is complex (theme fonts, default paragraph styles), so some indirectly inherited properties may not be fully covered. For formatting applied directly to paragraphs, accuracy is near 100%.

Can I batch-check multiple documents?

The current version checks one document at a time. For batch processing, upload and record results individually. Batch checking is on our roadmap for a future release.

Does it work when the template and document have very different structures?

Yes. DocxShuttle automatically maps document paragraphs to template rules (e.g., heading2 falls back to heading1). Unmatched paragraphs are listed separately without false positives. However, the larger the structural gap, the fewer items get checked.

Can the suggested fixes be applied directly to my document?

No. DocxShuttle is a read-only checker — it never modifies your files. Each suggestion tells you exactly which property to change in Word and what value to set. Apply the fix manually in Word.

Is DocxShuttle open source?

The core parsing and comparison logic is visible in the client-side source. Contact support@shuttlelab.org for full repository access.

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About DocxShuttle

A local-first format validator for Word documents

DocxShuttle is a browser-only utility from ShuttleLab focused on the pain points of academic and office document formatting. It parses .docx files against the OOXML standard and diffs them against a template — fonts, sizes, line spacing, indentation, alignment, and page margins — with clear suggestions for each problem.

Privacy First

All parsing happens locally; your files never leave your browser.

Works Offline

After the first load, the tool runs entirely offline.

Transparent

All rules are visible in the client-side source — nothing is hidden.

Run Your First Check

No account, no upload — your files stay in your browser

Questions or suggestions?

support@shuttlelab.org

Who is DocxShuttle for?

Graduate students and researchers who must match a university or journal Word template
Office workers drafting bids, government documents, or other format-strict files
HR staff producing employee contract templates that need compliance review
Editors proofreading formatting differences between a final manuscript and a style guide

When should I use DocxShuttle?

Your thesis draft is done but you don't know which parts violate the university template
You received an RFP that says "submit in the attached template format" and need a quick diff
A multi-author document has inconsistent fonts, spacing, and indentation that need unifying
Your submission was rejected for "formatting issues" but the reviewer didn't say what exactly
You pasted content from HTML into Word and need to reformat it to match a company template

How to upload a template and document for checking

Open the DocxShuttle homepage and click 'Start Checking'
In the template section, pick a built-in template or upload your own .docx template
In the document section, drag in or select the .docx file you want to verify
Click 'Run Check' and wait for parsing and comparison to finish

How to read the diff report

Look at the summary cards at the top: total checks, passed count, issue count
Filter by severity: high (font/size), medium (line height/paragraph), low (alignment/margin)
Click an issue to see expected vs. actual values and the suggested fix

How to fix formatting issues based on suggestions

Find the issue in the report and note the expected value (e.g., font size '小二', line height 1.5×)
Open the original Word document and navigate to the corresponding paragraph
In Word's Paragraph or Font dialog, change the property to the expected value from the report
Re-upload the document and run the check again to confirm the issue is resolved

DocxShuttle vs alternatives

Tool	Format Diff	Auto Suggestions	Local-Only	Free	No Install
DocxShuttle	✓	✓	✓	✓	✓
Word built-in Compare	— (content diff)	—	✓	✓	—
Manual template check	✓ (human)	—	✓	✓	✓
WPS template compare	Partial	—	Mixed	Partial	✓
Adobe Acrobat	— (PDF domain)	—	✓	—	—

Frequently Asked Questions

Is DocxShuttle free?: Yes — completely free. No account, no ads, no tracking. Every feature is available immediately.
Does my document get uploaded to a server?: No. All .docx parsing and format comparison runs in your browser's JavaScript runtime — your file never leaves your device. We don't log requests, don't run analytics on tool inputs, and don't store any check history.
Which Word file formats are supported?: Only .docx (Office Open XML) is supported. Legacy .doc and macro-enabled .docm files are not. If your file is .doc, save it as .docx in Word first.
Which formatting properties can it detect?: DocxShuttle checks 6 categories: font (CJK + Latin), font size, line height, paragraph (first-line indent, space before/after), alignment, and page margins (top/bottom/left/right). Each of the 20 paragraph roles (title, body, abstract, etc.) can have independent rules.
Is there a file size limit?: There is no hard file size limit — processing capacity depends on your browser's available memory. In practice, .docx files under 50 pages typically parse in 2-3 seconds. If the UI slows with very large files, close other browser tabs.
How accurate is the check? Can it miss issues?: DocxShuttle parses .docx files based on the OOXML standard and accurately extracts paragraph-level style properties. However, Word's style inheritance chain is complex (theme fonts, default paragraph styles), so some indirectly inherited properties may not be fully covered. For formatting applied directly to paragraphs, accuracy is near 100%.
Can I batch-check multiple documents?: The current version checks one document at a time. For batch processing, upload and record results individually. Batch checking is on our roadmap for a future release.
Does it work when the template and document have very different structures?: Yes. DocxShuttle automatically maps document paragraphs to template rules (e.g., heading2 falls back to heading1). Unmatched paragraphs are listed separately without false positives. However, the larger the structural gap, the fewer items get checked.
Can the suggested fixes be applied directly to my document?: No. DocxShuttle is a read-only checker — it never modifies your files. Each suggestion tells you exactly which property to change in Word and what value to set. Apply the fix manually in Word.
Is DocxShuttle open source?: The core parsing and comparison logic is visible in the client-side source. Contact support@shuttlelab.org for full repository access.