Practical guides
OpenToola Guides
Practical guides for PDF, image and privacy tools — written to help you get things done without uploading your files.
All OpenToola tools run locally in your browser. Your files are never uploaded.
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PDFHow to Merge PDF Files on Windows, Mac and iPhone (Free & Local)
Merge PDFs on Windows, Mac or iPhone without uploading them. A practical walkthrough, including the checks that keep the final file usable.
PDFHow to Sign a PDF on iPhone, Android and Computer (Without Printing)
Sign a PDF on iPhone, Android, Windows or Mac, place the signature where it belongs, and know when a simple signature is not enough.
ImageHEIC or JPG: What iPhone Photos Really Are, and When to Convert
Understand HEIC, when JPG is still needed, and how to convert iPhone photos without losing quality, location data or the original file.
PDFHow to Compress a PDF Without Destroying the Useful Part
Reduce a PDF for email or a portal, choose between structural and image compression, and check that text, links and signatures still work.
PDFPDF to JPG: Choose the Right Resolution Before You Convert
Turn PDF pages into JPG images for a website, a preview or a message, and understand what you lose when text becomes pixels.
PDFJPG to PDF: Turn Photos and Scans into a Document That Prints Properly
Combine JPG or PNG images into a PDF, fix orientation and page size problems, and avoid the usual blurry, sideways or oversized result.
PDFSplit a PDF: Extract the Pages You Need Without Re-Encoding Them
Extract pages or ranges from a PDF, understand the ZIP output, and choose between splitting and removing pages for the file you actually need.
PDFRemove Pages from a PDF: Delete Blanks, Duplicates and Confidential Sheets
Delete pages from a PDF without re-encoding the rest, check what removal can break, and avoid leaving sensitive content behind.
PDFRotate PDF Pages: Fix Sideways Scans Without Re-Encoding the File
Rotate one page or the whole PDF by 90, 180 or 270 degrees, understand page rotation metadata, and avoid breaking signatures or mixed layouts.
PDFOCR a PDF: Make a Scan Searchable Without Trusting Every Character
Turn a scanned PDF into searchable text or a searchable PDF, choose the right language, and check the mistakes OCR always makes.
ImagePassport Photo Requirements: The Rules That Get Photos Rejected
A practical guide to passport, visa and ID photos: size, background, expression, glasses, babies, printing and the mistakes that cause rejection.
ImagePassport Photo Sizes: Schengen, US, UK and Canada Compared
Compare the exact photo sizes, head proportions and digital rules for Schengen, US, UK and Canadian passports and visas, without guessing.
ImagePassport Photos for Arab Countries: Sizes for Saudi Arabia, UAE, Egypt and More
Compare passport and visa photo sizes for Saudi Arabia, the UAE, Egypt, Morocco, Algeria, Tunisia, Jordan and Iraq, with practical print and upload advice.
ImageCompress Images for the Web and Email Without Making Them Mud
Choose the right dimensions, quality and format for a photo that loads fast or fits an email, and know when compression is the wrong fix.
ImageResize Images for Social Media Without Stretching Faces
Choose the right dimensions for Instagram, Facebook, X, LinkedIn, YouTube and TikTok, crop before resizing, and avoid the PNG file-size trap.
ImageConvert PNG, JPG and WebP Without Losing Transparency or Detail
Choose the right image format, keep transparency, avoid repeated lossy conversions, and know when converting will make the file worse.
ImageImage to Text: What OCR Can Really Read from a Screenshot or Photo
Extract text from screenshots, receipts and photos, choose the right language, and know which images will defeat OCR before you waste time.
PDFReorder PDF Pages: Put a Scanned Bundle Back in the Right Order
Rearrange PDF pages with up and down controls, check what page reordering can break, and know when splitting or merging is the better tool.
PDFPDF Privacy: What Local Processing Protects and What It Does Not
Understand the real difference between browser-local PDF tools and cloud uploads, including metadata, extensions, shared devices and sync folders.
PDFDigital Signatures on PDF: Visual Mark, Certificate or Qualified Signature?
Tell the difference between a drawn signature, a cryptographic PDF signature and a qualified electronic signature, and know which one a document actually needs.
ImageDV Lottery Photo Requirements: Size, Head, Eyes and File Size
The exact DV Lottery photo rules: 600×600 to 1200×1200 px, JPEG under 240 KB, head 50–69%, eyes 56–69%, white background and no glasses.
ImageDV Lottery Photo Rejected? The Real Reasons and How to Fix Them
Why DV Lottery photos fail: wrong size, head ratio, background, glasses, file weight or selfie. Fix the file before submitting, without creating a duplicate entry.