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Tổng quan

Thông tin cơ bản & Tài khoản

Bảo vệ

Quyền riêng tư & An toàn

Đặc trưng

Công cụ & Giới hạn

Vấn đề

Lỗi & Sửa lỗi

PDF Converters

PDF ↔ Word, Excel, JPG, PPT

PDF Security Tools

Lock, unlock, sign & redact

Image Tools

Compress & convert images
Câu hỏi chung

FreePDFWorld có hoàn toàn miễn phí không?

Đúng! Tất cả các công cụ PDF của chúng tôi đều hoàn toàn miễn phí sử dụng. Không có phí ẩn, không có phí đăng ký và không có giới hạn về số lượng tệp bạn có thể xử lý.
Lời hứa của chúng tôi: Không cần thẻ tín dụng. Miễn phí mãi mãi.

Tôi có cần tạo tài khoản không?

Không cần đăng ký! Bạn có thể sử dụng tất cả các công cụ của chúng tôi ngay lập tức mà không cần tạo tài khoản. Đơn giản chỉ cần tải lên tập tin của bạn và nhận được kết quả của bạn.
Bảo mật & Quyền riêng tư

Dữ liệu của tôi có an toàn không?

Tuyệt đối. Chúng tôi rất coi trọng vấn đề bảo mật dữ liệu.
  • Mã hóa: Tất cả các hoạt động truyền đều sử dụng mã hóa SSL/TLS.
  • Tự động hóa: Tệp được xử lý tự động mà không có quyền truy cập của con người.
  • Xóa: Tệp sẽ bị xóa vĩnh viễn sau 1 giờ.
Các tập tin của bạn được xử lý trên các máy chủ an toàn, biệt lập.

Bạn giữ hồ sơ của tôi trong bao lâu?

Chúng tôi lưu giữ tệp trong tối đa 1 giờ để bạn có đủ thời gian tải chúng xuống. Sau đó, chúng sẽ bị xóa vĩnh viễn khỏi máy chủ của chúng tôi.
Đảm bảo tải xuống các tệp đã chuyển đổi của bạn ngay lập tức.
Tính năng & Giới hạn

Kích thước tập tin tối đa là bao nhiêu?

Kích thước tệp tối đa là 100 MB cho mỗi tệp. Điều này bao gồm 99% các tài liệu tiêu chuẩn.

Bạn có giữ nguyên định dạng không?

Đúng! Chúng tôi sử dụng các công cụ chuyển đổi cấp doanh nghiệp (như Aspose & LibreOffice) để đảm bảo bố cục, phông chữ và hình ảnh của bạn trông giống hệt trong tệp được chuyển đổi.
Khắc phục sự cố

Chuyển đổi của tôi không thành công. Tôi nên làm gì?

Nếu chuyển đổi không thành công, vui lòng kiểm tra:
  • Kết nối Internet của bạn có ổn định không?
  • Tệp có bị hỏng hoặc được bảo vệ bằng mật khẩu không?
  • Tệp có dưới 100 MB không?
Thử làm mới trang và tải lên lại.
PDF Converter Tools
PDF to JPG Converter

Is the PDF to JPG converter really free?

Yes — completely free with no registration, no account and no credit card required. Convert as many PDFs as you need.
No hidden fees. No watermark on the output images.

What quality are the output JPG images?

You can choose your output quality before converting: Standard (150 DPI) for lightweight files, High (300 DPI) — the default — for sharp, print-ready images, or Ultra‑High (500 DPI) for maximum detail. Higher DPI produces larger file sizes.

Single-page PDFs are delivered as a plain .jpg file. Multi-page PDFs are automatically packaged as a .zip archive containing one JPG per page — download the ZIP and extract to get all your images.

How many pages per PDF are supported?

Up to 50 pages per PDF are converted. Each page is exported as an individual JPG file. For longer documents, split your PDF first using our Split PDF tool.

Can I convert multiple PDFs at once?

Yes — batch convert up to 10 PDF files in a single upload. Each PDF is processed independently and yields one download per PDF: a plain JPG for single-page files or a ZIP archive for multi-page files.

Is my PDF file kept private during conversion?

All uploads are transferred over HTTPS/SSL. Files are processed in memory and are not permanently stored on our servers.
Download links expire after 5 minutes. Your documents are never shared with third parties.
JPG to PDF Converter

Is the JPG to PDF converter free?

Yes — 100% free, no registration or sign-up required. Simply upload your images and download the PDF instantly.
No watermark, no usage limits.

What image formats are supported?

The converter accepts JPG / JPEG, PNG, BMP, GIF and TIFF image formats. Each image is automatically scaled to fit an A4 page in the output PDF.

How many images can I convert at once?

You can upload up to 20 images in a single session. All valid images are merged into one multi-page PDF — each image on its own A4 page — and you receive a single download link for the result.

How is the image placed on the PDF page?

Each image is automatically scaled to fit within an A4 page with a small margin, preserving the original aspect ratio. The image is centered on the page for a clean, professional look.

Are all images merged into a single PDF?

Yes — automatically. All images you upload are merged into one multi-page PDF in the order they were selected. Each image occupies a separate A4 page. You receive a single PDF download.
Want to reorder or split pages later? Use our Merge PDF or Split PDF tools.
PDF to Word Converter

Is the PDF to Word converter free?

Yes — completely free with no registration, no account, and no credit card required.
No hidden fees. No watermark on the converted DOCX file.

Does the converter preserve fonts, tables, and formatting?

Yes. The conversion engine preserves text formatting (bold, italic, headings), fonts, colours, tables, bullet lists, and page layout as faithfully as possible. The result is a fully editable .docx file with native Word elements — not embedded images.

How many PDF files can I convert at once?

You can batch convert up to 5 PDF files in a single upload. Each PDF is converted independently and produces its own .docx download link.

Is my PDF kept private during conversion?

All uploads are transferred over HTTPS/SSL. Files are processed in memory on our servers and are never stored permanently or shared with third parties.
Download links expire after 5 minutes. Your documents remain fully private.

What happens with scanned or image-based PDFs?

Scanned PDFs (where each page is an image) produce limited editable text because there is no embedded text layer. For best results with scanned documents, consider running OCR first.
Text-based PDFs convert with highest accuracy. Scanned PDFs may have reduced fidelity.
Word to PDF Converter

Is the Word to PDF converter free?

Yes — 100% free with no sign-up or credit card required. Convert as many Word documents as you need.
No watermark. No usage limits. Instant conversion.

What Word file formats are supported?

Both .docx (Word 2007 and later) and .doc (older Word 97–2003) formats are fully supported. Upload either format and receive a professional PDF output.

How many Word files can I convert at once?

You can batch convert up to 5 Word files in a single upload. Each document is processed independently, and you get a separate PDF download link per file.

Does the output PDF look exactly like my Word document?

In most cases yes — the converter preserves fonts, images, tables, headers/footers, and page margins. Minor layout differences can occur if your Word document uses non-standard fonts or complex macros that are not embedded in the file.
For best results, embed all fonts in your Word document before uploading.

Is my Word document kept private?

All uploads use HTTPS/SSL encryption. Files are converted in memory and are never stored permanently on our servers or shared with any third party.
Download links expire after 5 minutes. Your documents are deleted immediately after processing.
PowerPoint to PDF Converter

Is the PowerPoint to PDF converter free?

Yes — completely free with no registration, no account and no credit card required.
No hidden fees. No watermark on the output PDF.

Which PowerPoint formats are supported?

Both .ppt (PowerPoint 97–2003) and .pptx (PowerPoint 2007 and later) are fully supported. Upload either format and receive a clean PDF.

Will fonts, images and slide layouts be preserved?

Yes. The conversion is powered by Aspose.Slides via our CoreDocEngine, which performs a high-fidelity render of every slide — preserving fonts, images, charts, shapes and background colours in the resulting PDF.

How many PowerPoint files can I convert at once?

You can batch convert up to 5 PowerPoint files in a single session. Each presentation is independently converted and produces its own PDF download link.
Large slide decks with many images may take up to 30 seconds each. Files are processed in parallel so total wait time is typically the same as one file.

Is my presentation kept private?

All uploads are transmitted over HTTPS/SSL. Files are processed in memory and deleted from our servers immediately after conversion. We never store, analyse or share your documents.
Download links expire after 5 minutes. Your presentations are never shared with third parties.

What is the maximum file size?

Each PowerPoint file can be up to 100 MB. For presentations with many high-resolution images, make sure the total file size stays within this limit.
Excel to PDF Converter

Is the Excel to PDF converter free?

Yes — completely free with no registration, no account and no credit card required. Convert as many Excel spreadsheets as you need.
No hidden fees. No watermark on the output PDF.

What Excel formats are supported?

Both .xls (Excel 97–2003) and .xlsx (Excel 2007 and later) formats are fully supported. Upload either format and receive a clean, professionally formatted PDF.

Will charts, formatting and multiple sheets be preserved?

Yes. The conversion is powered by Aspose.Cells via our CoreDocEngine, which performs a high-fidelity render of your spreadsheet — preserving cell formatting, font styles, colours, borders, embedded charts, images, and all worksheets. Each worksheet appears as a separate page in the output PDF.
Formula values are preserved in the PDF (as displayed), but formulas themselves are not recalculated on conversion.

How many Excel files can I convert at once?

You can batch convert up to 5 Excel files in a single session. Each file is processed independently in parallel, and you receive a separate PDF download link per file.
Large workbooks with many sheets or embedded charts may take up to 2 minutes each. Files are processed in parallel so total wait time is typically close to the longest single file.

Is my spreadsheet kept private during conversion?

All uploads are transmitted over HTTPS/SSL. Files are processed in memory on our servers and are never stored permanently or shared with any third party.
Download links expire after 5 minutes. Your spreadsheets are deleted immediately after conversion.

What is the maximum file size for Excel conversion?

Each Excel file can be up to 25 MB. For very large workbooks with many embedded images or charts, consider splitting the file into smaller workbooks before uploading.
PDF to Excel Converter

Is the PDF to Excel converter free?

Yes — completely free with no registration, no account and no credit card required. Convert as many PDF files to Excel as you need.
No hidden fees. No watermark on the output XLSX file.

What format will my converted file be in?

Your PDF will be converted to XLSX (Excel 2007 and later format). The output is fully compatible with Microsoft Excel, Google Sheets and LibreOffice Calc.

Will tables and data be preserved accurately?

Our converter uses Aspose.Cells via CoreDocEngine to reconstruct tables, rows, columns and cell content from your PDF as accurately as possible.
PDFs with complex multi-column layouts, merged cells, or scanned (image-only) content may require minor manual adjustment after conversion. For best results, use PDFs generated from digital documents rather than scans.

How many PDF files can I convert at once?

You can batch convert up to 5 PDF files in a single session. Each file is processed independently in parallel and you receive a separate XLSX download link per file.
Large PDFs with many tables or pages may take up to 2 minutes each. Files are processed in parallel so total wait time is typically close to the longest single file.

Is my PDF kept private during conversion?

All uploads are transmitted over HTTPS/SSL. Files are processed in memory on our servers and are never stored permanently or shared with any third party.
Download links expire after 5 minutes. Your PDFs are deleted immediately after conversion.
HTML to PDF Converter

Is the HTML to PDF converter free?

Yes — completely free with no registration, no account and no credit card required. Convert as many HTML files to PDF as you need.
No hidden fees. No watermark on the output PDF.

Will my CSS styles and formatting be preserved in the PDF?

Inline CSS styles and embedded <style> blocks are fully preserved. Text hierarchy (headings, paragraphs, lists), tables and base64-encoded embedded images are also retained.
Externally linked CSS files and image URLs will not load during server-side conversion — our engine runs in an isolated environment with no outbound network access. For best results, use self-contained HTML: inline styles, embedded <style> blocks, and images as Base64 data: URIs.

Are both .html and .htm file extensions supported?

Yes — both .html and .htm file extensions are accepted. Simply upload your file and click Convert to PDF.

How many HTML files can I convert at once?

You can batch convert up to 5 HTML files in a single session. Each file is processed independently in parallel and you receive a separate PDF download link per file.
Large or complex HTML documents may take up to 2 minutes each. Files are processed in parallel so total wait time is typically close to the longest single file.

Is my HTML file kept private during conversion?

All uploads are transmitted over HTTPS/SSL. Files are processed in memory on our servers and are never stored permanently or shared with any third party.
Download links expire after 5 minutes. Your HTML files are deleted immediately after conversion.
PDF Security Tools
Lock PDF — Password Protect

How do I add a password to a PDF?

Upload your PDF on the Lock PDF page, enter a password of your choice, and click Lock PDF. The download link for your password-protected PDF will be ready in seconds.
Free, instant, no registration required.

What encryption does FreePDFWorld use to lock PDFs?

FreePDFWorld applies AES-256 encryption — the same standard used by banks and governments. The resulting PDF cannot be opened without the correct password.
AES-256 is the strongest PDF encryption algorithm defined by the PDF specification (PDF 1.7+).

Can I set different passwords for opening vs. editing?

The Lock PDF tool sets a single open password that prevents anyone without the password from viewing the document. Owner/permissions passwords that restrict only editing or printing are handled separately — use the same tool's advanced options or contact us if you need custom permission restrictions.

Is my PDF kept private when I add a password?

All uploads are transmitted over HTTPS/SSL. Your file is processed in memory on our servers and is never stored permanently or shared with any third party.
Download links expire after 5 minutes. Your documents are deleted immediately after processing.
Unlock PDF — Remove Password

Can FreePDFWorld remove the password from any PDF?

FreePDFWorld can remove the password from any PDF you own and know the password for. You must enter the current open password to unlock the document — this is a legal and security requirement. We cannot and will not brute-force or bypass passwords on PDFs you do not have authorised access to.
Only use this tool on documents you own or have permission to modify.

What do I need to unlock a PDF?

Simply upload the password-protected PDF and enter its current open password. The tool will decrypt the file and produce a new, unlocked PDF ready for download — no further password required to open it.

Is the unlocked PDF kept private?

Yes. All uploads use HTTPS/SSL encryption. Files are processed entirely in memory and are never written to disk or shared with third parties. The download link expires in 5 minutes.
Your password is used only for the single decryption operation and is never logged or stored.

What is the maximum file size for Unlock PDF?

Each PDF can be up to 25 MB. For larger protected files, consider splitting the PDF first (if the PDF viewer allows it), or contact us for assistance.
Sign PDF — Digital Signature

What is a digital signature and how does FreePDFWorld sign PDFs?

A digital signature cryptographically binds your identity to a PDF document, proving the file has not been altered after signing. FreePDFWorld embeds a CMS (PAdES-compatible) detached signature using a server-side X.509 certificate via iText PdfSigner — the industry-standard Java PDF library.
The signature is visible in Adobe Acrobat's Signatures panel and is verifiable by any PDF reader that supports digital signatures.

Can I draw my own handwritten-style signature?

Yes. The Sign PDF tool includes an on-screen signature pad where you can draw your signature with a mouse, stylus or touch screen. Your drawn signature is embedded as a visible image on the page at the position you choose, and the file is additionally signed with a server-side cryptographic certificate.

Is the digital signature legally binding?

Digital signatures created with a valid X.509 certificate are legally recognised in many jurisdictions (e.g. EU eIDAS, US ESIGN Act). However, legal validity depends on the trust chain of the signing certificate and the applicable national regulations.
For legally binding contracts requiring a qualified electronic signature (QES), consult a qualified trust service provider in your jurisdiction.

How do I choose where the signature appears on the page?

After uploading your PDF, a preview of the first (or selected) page is shown. Click or tap the exact position where you want the signature block to appear. You can also select which page the signature should be placed on using the page selector in the tool.

Is my PDF kept private when signing?

All uploads use HTTPS/SSL encryption. The signing process runs entirely in memory on our server and the file is never stored permanently or shared with third parties.
Download links expire after 5 minutes. Your document is automatically deleted after processing.
Redact PDF — Remove Sensitive Information

What does PDF redaction do?

PDF redaction permanently removes sensitive text, images or other content from a document, replacing the redacted areas with solid black (or white) blocks. Unlike simply placing a black rectangle on top of text — which can be removed — true redaction eliminates the underlying content from the PDF structure itself.
Always verify the output PDF in a PDF reader to confirm sensitive content is fully removed before sharing.

Is redacted content permanently and irrecoverably removed?

Yes. FreePDFWorld's redaction tool uses iText to apply permanent redaction that removes the content from the PDF's object model — it is not merely covered up. The redacted areas cannot be recovered by selecting text, removing layers, or inspecting the raw PDF source.

What types of content can be redacted?

You can redact any rectangular region on any page, which covers:
  • Text (names, addresses, IDs, account numbers)
  • Images or photos embedded in the PDF
  • Signatures or stamps
  • Any other visible or invisible PDF object within the selected region

Can I undo a redaction?

No — redaction is permanent and irreversible in the downloaded PDF. Before downloading, you can adjust the redaction regions in the preview. Once you download the redacted file, the underlying content cannot be recovered. Always keep a copy of the original document in a secure location.
Keep a secure backup of the original, unredacted PDF before proceeding.

Is my PDF kept private during redaction?

All uploads are transmitted over HTTPS/SSL. Files are processed in memory and never stored permanently on our servers or shared with third parties. Download links expire after 5 minutes.
Your documents are automatically purged from memory after the download link expires.
Image Tools
Image Compressor

What image formats can I compress?

The Image Compressor supports JPEG, PNG, WebP, BMP and GIF files. You can also choose the output format — for example, convert a PNG to JPEG during compression to achieve significantly smaller file sizes.
JPEG is the most efficient format for photographs. PNG is better for logos and screenshots with text.

How much can the file size be reduced?

Compression savings vary by image content and chosen quality level. Typical results:
  • Light compression (80–90% quality) — 20–40% smaller, barely visible quality loss
  • Medium compression (50–70% quality) — 50–70% smaller, suitable for web use
  • High compression (20–40% quality) — 75–90% smaller, noticeable quality reduction
The preview shown after compression lets you judge quality before downloading.

Can I resize the image as well as compress it?

Yes — the compressor has an optional resize mode. You can resize by:
  • Exact dimensions — enter target width and/or height in pixels
  • Percentage — scale to a percentage of the original size (e.g. 50%)
  • Target file size — the tool automatically adjusts quality to hit a specified KB size
All resize modes preserve the aspect ratio by default.

Is there a target file size option?

Yes. Select the "Target Size (KB)" resize mode and enter your desired output size in kilobytes. The compressor will iteratively adjust the quality setting until the output is as close as possible to your target — ideal for email attachments or upload form limits.
Due to JPEG encoding characteristics, the actual output may be slightly above or below the exact target.

Is my image kept private during compression?

All uploads are transmitted over HTTPS/SSL. Your image is processed in memory on our servers and is never stored permanently or shared with third parties. The download link expires after 5 minutes.
Your images are automatically deleted from memory once the download link expires.

What is the maximum upload size for image compression?

Each image can be up to 25 MB. For very large RAW or TIFF images from a camera, consider saving them as standard JPEG/PNG first, which is also the most compatible format for web and social sharing.

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