- Bangla OCR: Tips for Better Results Practical tips for Bangla OCR: how to photograph a page, which settings to use, why conjunct letters and digits go wrong, and how to proofread the result. Read guide
- Bijoy vs Unicode: Converting Legacy Bangla PDF Text Why text copied from an old Bangla PDF looks like gibberish, how Bijoy and SutonnyMJ differ from Unicode, and how to convert it safely, with the limits. Read guide
- camt.052 vs camt.053 vs camt.054: Which Bank Message Is Which What the three ISO 20022 account messages are for, how they differ from MT940 and MT942, what versions .02 and .08 change and how to read each in a table. Read guide
- CSV Injection (Formula Injection) Explained How a cell starting with = + - or @ can become a formula when a CSV opens in Excel or Sheets, who is at risk, and how to export and clean CSV safely. Read guide
- DPI vs Pixels: What 300 DPI Really Changes DPI is a label, pixels are the detail. How to work out print size, why changing a file to 300 DPI adds no sharpness, and what forms usually really need. Read guide
- EPC QR Code (GiroCode) Explained What is inside an EPC QR code for SEPA payments: the fixed lines, field limits, the 331-byte rule, reference versus remittance, and why banking apps can differ. Read guide
- EPUB Accessibility Basics: Metadata, Structure and Checks What makes an EPUB accessible: discovery metadata, language, navigation, headings, alt text, tables, what an automated check can and cannot find, and the EAA. Read guide
- European Payment QR Codes Compared: EPC, SPAYD, PAY by square, Swiss QR-bill EPC QR (GiroCode), Czech SPAYD, Slovak PAY by square and the Swiss QR-bill compared: what each contains, where banks read it and which one to put on an invoice. Read guide
- Excel Print Settings Explained: Print Area, Scaling and Page Breaks Why an Excel sheet prints on too many pages, with a tiny font or without header rows: print area, fit to page, orientation, margins and page breaks explained. Read guide
- FatturaPA: XML vs XML.P7M Explained What an Italian e-invoice XML file is, what the .p7m signed envelope adds, how to open both, and why unwrapping a p7m is not the same as verifying the signature. Read guide
- Flattening PDFs: Forms, Annotations and Signatures What flattening a PDF does to form fields, comments, stamps and digital signatures, why it is not security, and when to keep an editable copy instead. Read guide
- GS1 Digital Link and Application Identifiers Explained How GS1 barcodes encode GTIN, batch, expiry and serial numbers with Application Identifiers, what FNC1 does, and how a GS1 Digital Link web address says the same. Read guide
- Hidden Metadata in Word, Excel and PowerPoint Files What Word, Excel and PowerPoint files reveal beyond the page: authors, comments, tracked changes, hidden sheets, notes, and what removing metadata does not fix. Read guide
- How PDF Text Extraction Differs From OCR Why extracting text from a PDF can return nothing, how that differs from OCR, and what OCR in this site's on-device editors can and cannot do. Read guide
- How to Check a PDF Before You Share It A routine for a PDF you are about to send: embedded files, personal data, text under black boxes, signatures, PDF/A and accessibility, with a tool for each step. Read guide
- How to Reduce an Image for Email and the Web Resize first, then compress: how much each step saves on a 2 MB photo, which format to pick, and the mistakes (repeat compression, PNG photos) that undo the savings. Read guide
- How to Tell If a PDF Is Structurally Valid Why a PDF that opens without errors can still be structurally damaged, what the checks look at, and what PDF tools on this site say when they cannot read a file. Read guide
- JPEG Quality and Quantization Tables Explained What the quality number of a JPEG is, how quantization tables work, why an estimate is not the original setting, and what subsampling and progressive coding mean. Read guide
- JPG vs PNG vs WebP: Choosing the Right Format How to choose between JPG, PNG and WebP for photos, screenshots and logos, with measured file sizes for each and the mistakes that make images bigger or blurrier. Read guide
- KSeF FA(3): How to Inspect an Invoice XML What a Polish KSeF FA(3) structured invoice contains, why a PDF is only a visualisation, how to recognise the format and how to read and schema-check the XML. Read guide
- KSeF KOD I: What the Invoice QR Code Contains What the KSeF verification QR code (KOD I) is, how its link is built from NIP, date and SHA-256 hash, what is printed under it and why KOD II is different. Read guide
- MSG vs EML: Two Ways to Save an Email What .msg and .eml email files are, how they differ, what each keeps, how to open them without Outlook and how to handle HTML mail and attachments safely. Read guide
- Mushak-6.3 Tax Invoice: The Fields Explained (মূসক-৬.৩) The fields of the Bangladesh Mushak-6.3 tax invoice (কর চালানপত্র) form column by column, how VAT and supplementary duty are calculated, and what to check yourself. Read guide
- N-Up and Booklet Printing Explained How N-up printing and fold-and-staple booklets work: pages per sheet, why booklets need multiples of four, the page order, duplex settings and creep. Read guide
- Office Macros, Embedded Objects and Outside Links Explained What in a Word, Excel or PowerPoint file can run code or load outside content, what a structural check can tell you, and what to check before you send a file. Read guide
- PAdES and eIDAS PDF Signatures Explained What a PDF signature check can and cannot tell you: integrity versus trust, simple, advanced and qualified signatures, PAdES levels B-B to B-LTA, timestamps and DSS. Read guide
- pain.001 Addresses: Structured, Hybrid and Unstructured What structured, hybrid and unstructured postal addresses are in a pain.001 payment file, why banks are phasing out unstructured ones, and how to fix a rejection. Read guide
- PDF Fonts: Embedded, Subset and Missing Explained What embedded, subset and missing fonts in a PDF mean, why the 14 standard fonts are special, how to read a font list, and how to fix missing fonts. Read guide
- PDF OpenAction and JavaScript: What They Do and Why They Matter What PDF OpenAction, additional actions, JavaScript, Launch and SubmitForm are, which ones run automatically, and how to inspect a file without running it. Read guide
- PDF Page Ranges Explained: Merge, Split and Extract How to write page ranges like 1-3,7 for splitting and extracting a PDF, recipes for deleting or reordering pages, and what each error message means. Read guide
- PDF Redaction Mistakes: Why Black Boxes Fail Why a black box over text in a PDF does not remove it, the common redaction failures, how to check a redacted file and what proper redaction does. Read guide
- PDF RGB vs CMYK: What Your Printer Needs RGB, CMYK, gray, spot colours and ICC profiles in a PDF for print, what an output intent and PDF/X are, and how to find and fix RGB objects before printing. Read guide
- Photo and Signature Size for Online Applications: Pixels, KB and Quality Meet an application portal's pixel size and KB limit for a photo or signature: crop, resize, then fit the JPEG quality, and what the portal may still reject. Read guide
- Swiss QR-Bill Data Explained What the QR code of a Swiss QR-bill contains: header, IBAN and QR-IBAN, QRR, SCOR and NON references, structured addresses, amounts and the 2.4 changes. Read guide
- The Searchable PDF: How an OCR Text Layer Works and Fails A scanned PDF becomes searchable through a hidden text layer on top of the picture. How it is built, how it goes wrong, and how to measure whether it fits. Read guide
- Understanding Image Color Profiles What an embedded color profile does, why CMYK or Adobe RGB images can look wrong on the web, which of this site's tools drop profiles, and how to check a file. Read guide
- Upload Requirements Checklist: Size, Pages, Paper, Text and Resolution The technical reasons portals reject documents (size, paper, pages, password, text layer, dpi, metadata) and how to check a file before uploading. Read guide
- VeriFactu QR Code: What Is in It and How to Read It What the VeriFactu invoice QR code contains (NIF, number, date, amount), its size and format rules, what a reader can check and what only the AEAT can tell you. Read guide
- What Content Credentials Actually Tell You What C2PA Content Credentials are, what a valid or missing manifest does and does not prove, why trust lists matter, and why it is not an AI-image detector. Read guide
- What EXIF and GPS Metadata Reveals, and How to Remove It What EXIF, GPS and other hidden data in a photo can reveal, how to check for it, and how to remove it without re-encoding the picture. What removal does not cover. Read guide
- Why a Filled PDF Form Looks Blank or Prints Empty A PDF form field stores its value and its drawing separately, and printing follows different rules from the screen. What goes wrong and how to check it. Read guide
- Why Text Copied From a PDF Turns Into Symbols A PDF stores glyphs, not text. How the ToUnicode map decides what you get when you copy, and what to do when copy and paste gives boxes or wrong letters. Read guide
- Word Heading Structure: Styles, Levels and Numbering How heading styles, outline levels and multilevel numbering hold a long Word document together, and the mistakes that break the contents and navigation. Read guide
- ZUGFeRD vs Factur-X vs XRechnung: What Is the Difference? What ZUGFeRD, Factur-X and XRechnung are, how they relate to EN 16931, UBL and CII, what the five hybrid profiles mean and how to tell which one a file is. Read guide