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Guides about PDFs grounded in measurement and the specification: where file size actually goes, why redaction fails, and more.
In depth
How to redact a PDF properlyA black rectangle is not redaction — the text stays in the file and copy-paste reveals it. We demonstrate the failure, show the PDF syntax behind it, and explain what actually removes the content.2026-08-31Why is my PDF so large?Median image share in PDFs under 1 MB: 0%. We measured 22 public documents (1,726 pages) at the object level — in small files the bytes are fonts and form fields, so compressing images does nothing.2026-08-31Haven PDF helpHow to use Haven PDF: opening files, the full keyboard shortcut list, working offline, password-protected PDFs, what the browser can and cannot do, and fixes for common problems.2026-08-31
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Compress PDF to 100KBCompress PDF to 200KBCompress PDF to 1MBPDF Too Large to Email? Fix It in SecondsMerge PDF Files on iPhoneMerge PDF Files on AndroidSign a PDF Without AdobeFlatten a PDF FormRemove a Password from a PDFOCR a PDF — Free and Without UploadingConvert a PDF to Black and WhiteDelete One Page from a PDFAn iLovePDF Alternative That Never Uploads Your FilesA Smallpdf Alternative Without Uploads or Task LimitsA Free Adobe Acrobat Alternative for Everyday PDF WorkA Sejda Alternative Without Daily Limits or UploadsA PDF24 Alternative That Works on Every DeviceHow to Add a Watermark to a PDFHow to Password-Protect a PDFHow to Add Page Numbers to a PDFHow to Convert JPG Images to a PDFHow to Split a PDF into Separate FilesHow to Rotate a PDF and Actually Save ItHow to Crop the Margins of a PDFHow to Edit Text in a PDFHow to Convert a PDF to JPG ImagesHow to Extract Text from a PDFHow to Extract Images from a PDFHow to Reorder the Pages of a PDFHow to Create a Blank PDFHow to Convert a PDF to WordHow to Convert a Word Document to PDFCompress PDF to 500KBCompress PDF to 2MBTurn a photo into a scanned PDFFill and sign a PDFMerge PDFs without uploadingSign a PDF on iPhoneBlank A4 PDF — create and downloadBlank A5 PDF — create and downloadEdit a PDF without a watermarkPrint a PDF as a bookletPDF editor for MacPDF editor for AndroidPDF editor for WindowsPDF editor for Linux2026-08-31