Guides
Why a file is too big to send, which format to pick, what a password really protects — explained step by step, with the free tool for each job.
PDF guides
- Why is my PDF so large?A three-page PDF shouldn't be 40 MB. Learn what really makes PDFs big — scans, phone photos, fonts, saved edits — and how to shrink each one.
- How to make a PDF small enough to email or uploadPDF too large to email or rejected by an upload form? Hit a size like 10 MB, 2 MB or 500 KB without making the text unreadable.
- KB vs MB: how to check and meet file upload size limitsIs 1 MB 1,000 KB or 1,024 KB? Both, depending on who's counting. How to read file sizes on any device and get files under a form's upload limit.
- How to scan double-sided documents without a duplex scannerNo duplex scanner? Scan the fronts, flip the stack, scan the backs, then put the pages back in order. Step by step, with fixes for common problems.
- The best scan settings for documents: resolution, colour and file sizeWhich resolution and colour mode to scan documents at, how each choice affects file size, and when a phone does the job as well as a scanner.
- Why PDFs lose their formatting when you convert them to WordConverted a PDF and got a mess of text boxes or plain paragraphs? Why PDFs don't convert cleanly to Word, which files do, and what to use instead.
- How to prepare a PDF for ChatGPT and other AI assistantsGet better answers about a PDF from an AI assistant: extract clean text or Markdown, split long files and remove personal details before you paste.
- How to redact a PDF properly, and why black boxes failA black rectangle over text doesn't remove it — the words can still be copied out. How real redaction works, what it misses and how to check your file.
- PDF passwords explained: open passwords and permission passwordsWhy one PDF asks for a password and another just won't let you print. The two kinds of PDF password, what they protect and how to remove them.
- How to sign a PDF without printing itFill in a PDF form, add your signature and lock the answers — no printer, no scanner, no account. Plus when a simple signature isn't enough.
- Bates numbers explained: what they are and how they workWhat a Bates number like SMITH000001 means, the conventions behind prefixes and zero padding, and how it differs from ordinary page numbers.
- Are online PDF tools safe? What happens to your filesWhat really happens when you upload a PDF to an online converter, the risks for sensitive documents, and how to check a tool keeps files on your device.
Image guides
- HEIC vs JPG: what's the difference, and which should you use?iPhone photos saved as HEIC won't open on some PCs, Android apps or upload forms. Learn how HEIC differs from JPG and how to convert or avoid it.
- How to reduce a photo or signature to 20, 50, 100 or 200 KBJob, exam and visa portals often want a photo or signature under 20–200 KB at set dimensions. Here's how to hit both limits and keep it legible.
- JPG, PNG, WebP or AVIF: which image format should you use?Photos, screenshots, logos, websites or email? A plain comparison of JPG, PNG, WebP and AVIF — size, quality, transparency and where each one opens.
- How to remove location data from your photosPhone photos can carry the exact GPS spot where they were taken. Learn what EXIF metadata reveals, when it's shared, and how to strip it first.
- Social media image sizes: how to fit photos without bad cropsThe shapes and pixel sizes that work for Instagram posts and Stories, YouTube thumbnails and profile pictures — and how to fit a photo without awkward crops.
- Favicon sizes explained: which icon files your site needsWhich favicon files a website actually needs — favicon.ico, a 180 px Apple touch icon, 192 and 512 px PNGs — and the HTML tags that connect them.
Video guides
- What to do when a video is too big to sendVideo too large for email, WhatsApp, Discord or an upload form? See what makes videos big and how to get under a limit by compressing, trimming or splitting.
- Why iPhone videos won't play everywhere — and how to fix itiPhone videos are MOV files, often in HEVC (H.265). Learn why some PCs, TVs and upload sites reject them, and how to get a version that plays.
- GIF vs MP4: which should you use?Why a few seconds of GIF can outweigh a whole MP4, why GIFs look grainy, when GIF is still the right choice, and how to make a small one from a clip.
- How to turn a landscape video into a vertical or square oneTurn a landscape video into 9:16 vertical or 1:1 square for Reels, TikTok and Shorts: crop vs fit with bars, keeping the subject in frame, and safe zones.
- SRT vs VTT: subtitle formats, burned-in captions and syncSRT and WebVTT look almost the same but aren't interchangeable. See how they differ, soft vs burned-in captions, and how to fix subtitles that are out of sync.
Audio guides
- MP3, M4A, WAV, FLAC and OGG comparedLossy or lossless, how big each format gets per minute, what plays where, and which audio format to pick for music, voice, editing and sharing.
- How to make a ringtone from a song or recordingCut the best part of a song, voice note or video, add a smooth fade, and save it in the right format for Android or iPhone — free, in your browser.
- Audio too quiet? How to make it louder without wrecking itNormalize or boost the volume? What each one does, why loud audio crackles, and how to fix a recording you can only hear in one ear.