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Plain answers for everyday file jobs: exam photo sizes, shrinking PDFs, picking image formats and more. Each one links to a free tool that does it in your browser.

Image tools Exam & form photos PDF tools Text tools Developer tools Calculators

Image tools

Image tools · 23 Oct 2026600 x 600 Photo Size: How to Make a 600x600 Photo (US Visa, DV)What a 600 x 600 photo is, how to make one on phone or PC, and the US visa and DV lottery rules: square JPEG, 2 x 2 inch, under 240 KB.Image tools · 23 Oct 2026AVIF vs WebP vs JPG: File Size, Support and When to Use EachAVIF vs WebP compared with JPG: file size, quality, browser support and encoding speed, plus which format to use for websites, forms and sharing.Image tools · 23 Oct 2026Compress a Photo to 500 KB or 1 MB Without Losing QualityShrink a phone photo to under 1 MB or 500 KB in seconds, keep it sharp, and see how to do it with Paint on Windows if you prefer.Image tools · 23 Oct 2026Compress Image to 100 KB Without Losing Quality (JPG Guide)Reduce a photo to under 100 KB while keeping it sharp: the right pixel size, JPG quality and order of steps, on phone or PC, free.Image tools · 23 Oct 2026Compress Image to 200 KB Free (JPG, Also 150 KB) – Phone & PCReduce a photo below 200 KB or 150 KB as a JPG for NEET, UPSC and other forms, on phone or PC, free and without uploading it anywhere.Image tools · 23 Oct 2026Compress Image to 30 KB in JPG (Also 40 KB and 30 KB PDF)Get a photo or signature under 30 KB or 40 KB as a JPG on phone or PC, keep it sharp, and make a 30 KB PDF when a form asks for one.Image tools · 23 Oct 2026Convert PNG or JPG to WebP Without Losing QualityHow to convert PNG and JPG to WebP without visible quality loss, when to use lossless vs lossy WebP, bulk conversion, and using WebP on WordPress.Image tools · 23 Oct 2026Crop Image to Passport Size: in cm, Pixels or KB (Phone, Mac, PC)Crop any photo to passport size (3.5 x 4.5 cm or 2 x 2 inch), then set exact cm, pixels and KB. Free in your browser, plus Mac and laptop methods.Image tools · 23 Oct 2026Flip Image Left to Right, Mirror a Selfie or Rotate 90 DegreesFlip an image left to right, fix a mirrored selfie, or rotate a sideways photo 90 degrees so it uploads the right way up. Phone, laptop and iPhone.Image tools · 23 Oct 2026HEIC vs JPG: Open and Convert iPhone Photos on Windows & AndroidWhat HEIC is, why your iPhone uses it, how to open HEIC on Windows and Android, and how to convert it to JPG for forms and sharing.Image tools · 23 Oct 2026How to Change iPhone Photos from HEIC to JPG (and Stop HEIC)Switch your iPhone camera to JPG with the Most Compatible setting, convert existing HEIC photos to JPG on PC or phone, and keep the quality high.Image tools · 23 Oct 2026How to Compress Image Size in Laptop (Windows & Mac, in KB)Reduce image size on a Windows or Mac laptop with Paint, Photos, Preview or a browser tool, and hit an exact KB limit without installing software.Image tools · 23 Oct 2026How to Compress Image Size in Mobile (Android & iPhone, No App)Reduce photo size on Android or iPhone in your browser, no app needed. Hit an exact KB, handle HEIC, and send full-size photos on WhatsApp.Image tools · 23 Oct 2026How to Compress Images for a Faster Website (LCP & WebP Guide)Images are often the heaviest part of a page. Learn the right dimensions, formats and file sizes to improve Core Web Vitals and LCP.Image tools · 23 Oct 2026How to Compress JPEG File Size (Quality Settings, 50 KB, 150 KB)Reduce JPEG file size the right way: what quality setting to use, how to hit 50 KB or 150 KB, and whether JPEG and JPG are different.Image tools · 23 Oct 2026How to Compress PNG Without Losing Quality (Keep Transparency)Shrink PNG files while keeping them sharp and transparent, get a PNG under 100 KB, and know when converting to JPG or WebP is the smarter move.Image tools · 23 Oct 2026How to Convert JPG to PNG with a Transparent BackgroundConverting JPG to PNG does not remove the background by itself. Here is how to get a real transparent PNG on iPhone, Android, Mac and Windows.Image tools · 23 Oct 2026How to Convert WebP to JPG on Windows, Mac and PhoneSaved an image and got a .webp file? Here is why it happens, how to open WebP, and how to convert WebP to JPG on Windows, Mac, Android and iPhone.Image tools · 23 Oct 2026How to Make a Passport Size Photo at Home (India & US)Take and crop a passport size photo at home: India 35 x 45 mm, US 2 x 2 inch, plus background, face size, glasses and printing tips.Image tools · 23 Oct 2026How to Print Passport Size Photos at Home (A4, 4x6, Word)Print passport size photos at home: fit 8 on 4x6 or 25–30 on A4 in Word, the right print settings and paper, and how to keep the size exact.Image tools · 23 Oct 2026How to Resize Image in KB (20 KB to 50 KB, 50 KB to 100 KB)Change an image's file size in KB, make it bigger or smaller to fit a range like 20–50 KB, and understand KB vs pixels so forms accept it.Image tools · 23 Oct 2026How to Watermark Photos for Free (Name, Text, ID Copies)Add a free text watermark to photos or PDFs in your browser: your name, website or 'for KYC only' on ID copies. Batch, tiled, no upload, no sign-up.Image tools · 23 Oct 2026Image Size, Resolution & DPI Explained: Resize in cm, mm, InchesPixels, DPI and cm finally make sense. Learn the one formula behind every 'resize to 3.5 x 4.5 cm' instruction, with worked examples.Image tools · 23 Oct 2026Instagram Post Size & Ratio: Pixels for Posts, Stories, ReelsInstagram post size ratio and pixels: 4:5 portrait 1080x1350, square 1080x1080, stories and reels 1080x1920, profile picture, and posting without cropping.Image tools · 23 Oct 2026JPG vs PNG vs WebP: Which Image Format to Use and WhenA plain guide to JPG, PNG and WebP: how each one compresses, when to pick it, and which to use for websites, forms, logos and screenshots.Image tools · 23 Oct 2026Passport Size Photo Size in cm, Inches & Pixels (India, US, UK)Passport size photo dimensions in cm, mm, inches and pixels for India, the US and the UK, with the 7:9 ratio explained and how to make one free.Image tools · 23 Oct 2026PNG to JPG Under 100 KB (or 50 KB, 200 KB) in High QualityConvert a PNG to a JPG under 100 KB in one step, keep it sharp, and hit 50 KB or 200 KB limits too. Works on iPhone, Android and PC.Image tools · 23 Oct 2026Resize Image in cm and KB (JPG Format): 6 x 2 cm, 3.5 x 4.5 cmResize a photo or signature to an exact size in cm and a KB limit in one step. Includes cm to pixels at 200 and 300 DPI, Paint and Mac steps.Image tools · 23 Oct 2026WebP to PNG: Save WebP as PNG With Transparency KeptConvert WebP to PNG in your browser without losing quality or the transparent background. Steps for Windows, Mac, Android and iPhone.Image tools · 23 Oct 2026What Is AVIF? How to Convert AVIF to JPG or PNGWhat an AVIF file is, why websites serve it, how to open AVIF on Windows and Mac, and how to convert AVIF to JPG or PNG for free in your browser.Image tools · 23 Oct 2026What Is JPEG XL (JXL)? Open, Convert and Browser SupportJPEG XL explained: what a .jxl file is, how it compares with JPG, lossless JPG to JXL, how to open JXL files and convert JXL to JPG or PNG.Image tools · 23 Oct 2026WhatsApp DP Full Photo Without Crop: Fit Any Photo in a SquareSet a full photo as your WhatsApp DP without cropping: fit it inside a square with white borders, then upload. Also DP size and how to change it.Image tools · 23 Oct 2026YouTube Thumbnail Size & Ratio: 1280x720, Shorts, MB LimitYouTube thumbnail size ratio is 16:9. Use 1280x720 or larger, JPG or PNG, under the 2 MB mobile limit. Plus Shorts thumbnails and how to change one.

Exam & form photos

Exam & form photos · 23 Oct 2026How to Compress Image to 10 KB (Photo, Signature, Passport)Reduce any photo or signature to under 10 KB on phone or PC without it turning to mush. Includes 10–20 KB ranges and passport photo tips.Exam & form photos · 23 Oct 2026How to Make Your Signature Clear for Online Forms (Scan & Crop)Faint, grey or blurry signature rejected? Fix it with the right paper, pen, light, crop and black-and-white conversion, then hit the exact size.Exam & form photos · 23 Oct 2026How to Reduce Photo Size to 20 KB or 50 KB for Exam FormsGet your photo under 20 KB or 50 KB for SSC, IBPS, NEET and other forms on phone or PC, without turning it blurry or getting it rejected.Exam & form photos · 23 Oct 2026IBPS & SBI Photo, Signature, Thumb & Declaration Size GuideIBPS and SBI upload sizes for photo, signature, left thumb impression and handwritten declaration, with the declaration rules that cause most rejections.Exam & form photos · 23 Oct 2026IBPS Handwritten Declaration Format: What to Write and SizeWhat to write in the IBPS handwritten declaration, the rules (English, own handwriting, not capitals) and the 800 x 400 px, 50–100 KB upload size.Exam & form photos · 23 Oct 2026IBPS Left Thumb Impression Size: 240x240 px, 20–50 KBIBPS left thumb impression size is 240 x 240 px at 200 DPI, 20–50 KB JPG. How to take a clear print at home and resize it for PO, Clerk and RRB.Exam & form photos · 23 Oct 2026NEET, JEE & CUET Photo and Signature Size: NTA Upload GuideNTA upload rules for NEET, JEE Main and CUET: photo, postcard photo, signature, thumb impressions and PDFs, with the ranges sources agree on.Exam & form photos · 23 Oct 2026PAN Card Photo Size and Signature Size: NSDL (Protean) vs UTIPAN card photo size is 3.5 x 2.5 cm; signature about 2 x 4.5 cm. Pixel and KB limits for Protean (NSDL) and UTIITSL uploads, and when no photo is needed.Exam & form photos · 23 Oct 2026Photo Not Uploading in Online Form? 10 Fixes That WorkPhoto not uploading in an online form? Fix 'invalid file format', 'file size too large', IBPS 'corrupted image' and JPG errors on phone or PC in minutes.Exam & form photos · 23 Oct 2026Photo Rejected in Application Form? Reasons and How to FixWhy exam and job forms reject photos: background, glasses, cap, blur, old photo, wrong size. How to fix each one and re-upload before the window closes.Exam & form photos · 23 Oct 2026RRB Photo Size and Signature Size: NTPC, Group D, ALP GuideRRB photo and signature size for NTPC, Group D and ALP: the live photo, the 30–49 KB signature, older 30–70 KB specs and the SC/ST certificate upload.Exam & form photos · 23 Oct 2026SSC Photo and Signature Size: CGL, CHSL, MTS, GD GuideSSC photo and signature size explained: KB limits, dimensions, the live photo rule and why sources disagree. Check this before you fill the SSC form.Exam & form photos · 23 Oct 2026SSC Photo Resize With Name and Date: Is It Still Needed?Does the SSC photo need a name and date? What older notices said, how the live photo changed it, and how to make a 20–50 KB, 3.5 x 4.5 cm photo if asked.Exam & form photos · 23 Oct 2026SSC Signature Size in KB and cm: 10–20 KB JPG ExplainedSSC signature size is a 10–20 KB JPG. Why guides quote 4 x 2 cm, 6 x 2 cm, 140 x 60 or 236 x 79 px, and how to make one for CGL, CHSL, JE or CPO.Exam & form photos · 23 Oct 2026UPSC Photo Size With Name and Date: 2026 Rules and 3/4 FaceUPSC photo rules: 20–200 KB JPG, white background, face covering 3/4 of the frame, plus what changed about name and date on the photo and the live photo.Exam & form photos · 23 Oct 2026UPSC Triple Signature: Size, Pixels and How to Upload ItUPSC now wants three signatures, one below the other, in one image. Size in KB and pixels, how to sign and resize it, and mistakes that get it rejected.

PDF tools

PDF tools · 23 Oct 2026Add Page Numbers to PDF From a Specific Page (Free, No Acrobat)Number a PDF starting from page 2, 3 or any page, skip the cover and contents, use Page X of Y, and choose the position. Free, no Acrobat needed.PDF tools · 23 Oct 2026Compress PDF to 100 KB Without Losing Quality (Free, Online)Reduce a PDF to 100 KB for forms and portals while keeping text readable. What really works for scanned certificates, on phone or PC, free.PDF tools · 23 Oct 2026Compress PDF to 500 KB or 1 MB Without Losing Quality (Free)Get a PDF below 500 KB or under 1 MB for job, visa and university portals. Keeps text sharp, works on phone or laptop, files stay on your device.PDF tools · 23 Oct 2026How to Arrange PDF Pages in Order (Online, Free, iPhone too)Put PDF pages in the right order, fix a scan that came out reversed or with fronts and backs separated, rotate sideways pages and delete blanks. Free.PDF tools · 23 Oct 2026How to Compress a PDF for Email (Gmail, Outlook, WhatsApp)PDF too big to email? Gmail and Outlook.com cap messages at 25 MB. Here's how to compress a PDF to fit, and when splitting or a link is the better fix.PDF tools · 23 Oct 2026How to Compress a PDF in Mobile (Android & iPhone, No App)Compress a PDF on your Android phone or iPhone without installing an app. Works for scanned PDFs and exact KB limits like 200 KB, free and private.PDF tools · 23 Oct 2026How to Compress a PDF to 2 MB for Email and Upload PortalsReduce a PDF to under 2 MB for portal uploads and email attachments. Free, works on phone or PC, keeps documents readable, nothing uploaded.PDF tools · 23 Oct 2026How to Compress a PDF to 300 KB (or 400 KB) Online FreeReduce a PDF to under 300 KB for exam, scholarship and job portals. Works on phone or PC, keeps text readable, and nothing is uploaded.PDF tools · 23 Oct 2026How to Compress a PDF to Under 200 KB (or 100 KB) for Govt PortalsShrink a scanned certificate or form PDF below 200 KB or 100 KB for government and exam portals while keeping the text readable.PDF tools · 23 Oct 2026How to Convert Image to PDF on iPhone or Android (No App)Turn photos into a PDF on your iPhone or Android phone, one image or many, without installing an app. Plus how to keep the file small for uploads.PDF tools · 23 Oct 2026How to Delete Pages from a PDF for Free (Mobile & PC)Remove blank or unwanted pages from a PDF for free, on mobile or PC, without Acrobat. Type page numbers or pick them visually. No upload.PDF tools · 23 Oct 2026How to Extract Pages from a PDF (New PDF, Separate Files, JPG)Pull selected pages out of a PDF into a new file, into separate PDFs, or as JPG images. Free, no upload, no Acrobat needed, on phone or PC.PDF tools · 23 Oct 2026How to Merge PDF and JPG into One PDF (Mobile, Laptop, Mac)Combine a PDF and image files into a single PDF in the right order. Free steps for phone, Windows laptop and Mac, with no upload and no watermark.PDF tools · 23 Oct 2026How to Merge, Split & Reorder PDF Pages for ApplicationsCombine certificates into one PDF, pull out the pages you need, fix page order and rotation, then shrink it under the upload limit. Step by step.PDF tools · 23 Oct 2026How to Rotate a PDF File and Save It Permanently (Free)Rotate all pages or just one page of a PDF and save it so it stays fixed. Free on laptop or mobile, no Acrobat, no upload.PDF tools · 23 Oct 2026How to Scan Documents with Your Phone and Combine Into One PDFScan certificates and forms with your Android phone or iPhone, then merge the pages into one clean, small PDF ready to upload or email.PDF tools · 23 Oct 2026How to Split a PDF into Multiple Files (2, 3 or More Parts)Split a PDF into separate files: every page, custom ranges, or equal parts. Free, no upload, works on phone, Windows and Mac. Download all as a ZIP.PDF tools · 23 Oct 2026How to Watermark a PDF for Free (DRAFT, CONFIDENTIAL, Name)Add a DRAFT, CONFIDENTIAL or name watermark to every page of a PDF for free. Online vs Mac Preview vs Word, plus the truth about removing watermarks.PDF tools · 23 Oct 2026iLovePDF Alternative With No Upload: Private, Free PDF ToolsWant an iLovePDF, Smallpdf, 11zon or Pi7 alternative that doesn't upload files? What browser-only PDF tools do, their limits, and how to check.PDF tools · 23 Oct 2026Is It Safe to Use Online PDF and Image Tools? Where Files GoWhat really happens when you upload a file to an online PDF or image tool, how in-browser processing differs, and how to check any tool yourself.PDF tools · 23 Oct 2026JPG to PDF Under 200 KB (or 100, 300, 500 KB) for FormsTurn one or many JPG photos into a single PDF under 200 KB, 100 KB or 500 KB for exam and job portals, without making the text unreadable.PDF tools · 23 Oct 2026PDF to JPG Under 100 KB (or 50 KB, 200 KB) for UploadsConvert a PDF certificate or page to a JPG under 100 KB, 50 KB or 200 KB for forms that only accept images, while keeping it readable.PDF tools · 23 Oct 2026PDF to PNG in High Quality: DPI, Mac & Transparent BackgroundConvert PDF pages to sharp, lossless PNG images. Which DPI to pick, how to do it on Mac, and the honest answer on transparent backgrounds.PDF tools · 23 Oct 2026PNG to PDF in High Quality: Screenshots, A4 & MergingConvert PNG images and screenshots to a sharp, high quality PDF. Combine many PNGs into one file, choose A4 or no margins, and keep text crisp.

Text tools

Text tools · 23 Oct 2026Character Count Limits: X, Instagram, LinkedIn, SMS & SEOCharacter counter with spaces explained, plus the limits that matter: X posts, Instagram bios, LinkedIn, SMS 160, YouTube titles and meta descriptions.Text tools · 23 Oct 2026How Long Is a 500-Word Essay? Word Limits, Pages & Reading Time500 words is about 1 page single-spaced or 2 double-spaced. See pages, reading time, SOP and college essay limits, and how to stay within them.Text tools · 23 Oct 2026How to Check Word Count in a PDF, Google Docs, Word & PowerPointHow to word count a PDF, plus the exact menus for Google Docs, MS Word, Pages and PowerPoint, and why different tools give slightly different counts.Text tools · 23 Oct 2026How to Convert Case in Word & Excel (UPPER, lower, Title)How to convert case in Word with Shift+F3 or Change Case, use UPPER, LOWER and PROPER in Excel, and get sentence case or title case online.Text tools · 23 Oct 2026How to Remove Duplicate Lines: Online, Excel, Notepad++, LinuxRemove duplicate lines online in one paste, or in Excel, Notepad++, VS Code and Linux with sort -u, uniq and awk. Keep the original order if you need to.Text tools · 23 Oct 2026How to Remove Line Breaks from Text Copied from a PDFRemove line breaks from text copied from a PDF in one click, or with Word find and replace (^p), Excel CHAR(10) and Notepad++. Keep paragraphs intact.Text tools · 23 Oct 2026How to Sort Lines Alphabetically (Word, Excel, Docs, Notepad++)Sort lines alphabetically online, or in Word, Excel, Google Docs, Notepad++ and Linux. Plus sorting by number or length, and why 10 comes before 2.

Developer tools

Developer tools · 23 Oct 2026How to Check the SHA-256 Hash of a File (Windows, Mac, Linux)Check a file's SHA-256 hash with certutil or PowerShell on Windows, shasum on Mac, sha256sum on Linux, or in your browser. Verify downloads properly.Developer tools · 23 Oct 2026How to Convert an Image to a Base64 String (and Back)Convert any image to a Base64 string or data URI for HTML, CSS and JavaScript, decode Base64 back to an image, and know when the size overhead is worth it.Developer tools · 23 Oct 2026How to Create a Strong Password You Can Actually ManageLength beats complexity. Learn how long a password should be, how passphrases work, and how a password manager makes strong passwords painless.Developer tools · 23 Oct 2026How to Decode a Base64 Encoded String (Linux, JS, Python)How to decode a Base64 encoded string online or with Linux, PowerShell, JavaScript atob/btoa and Python, and why Base64 is not encryption.Developer tools · 23 Oct 2026How to Decode a URL Encoded String (%20 and More Explained)Decode URL encoded strings like %20 and %3A online or in JavaScript, Python, Java and C#. Learn encodeURIComponent, + vs %20 and query strings.Developer tools · 23 Oct 2026How to Generate a UUID: Online, Python, JavaScript, SQL & ExcelHow to generate a UUID online or in Python, JavaScript, Java, PostgreSQL, Linux and Excel, plus UUID v4 vs v7 and what a Minecraft UUID really is.Developer tools · 23 Oct 2026JSON Formatter and Validator: Fix Common JSON Errors FastFormat and validate JSON privately, understand errors like trailing commas and single quotes, and format JSON in VS Code, Notepad++ or the terminal.Developer tools · 23 Oct 2026Password Generator 16 Characters: Is 8, 12 or 16 Enough?Should a password be 8, 12 or 16 characters? See the real maths for each length, when a word-based passphrase is better, and how to make one.Developer tools · 23 Oct 2026QR Code Generator for Location, Wi-Fi, UPI & Contacts (Free)Make a QR code for a Google Maps location, Wi-Fi password, UPI payment or contact card, with the exact text to paste. Static codes that never expire.Developer tools · 23 Oct 2026Static vs Dynamic QR Codes: Which to Use & Why Free Ones Stop WorkingYour printed QR code suddenly shows an error or an ad? Here is the difference between static and dynamic QR codes, and how to pick the right one.

Calculators

Calculators · 23 Oct 2026Age Calculator for Exam Age Limit: Check Age as on Cut-off DateCheck your exact age on an exam's cut-off date, read 'born not earlier than' rules correctly, and add OBC/SC/ST age relaxation the right way.Calculators · 23 Oct 2026BMI Calculator in kg and Feet: Formula & Indian BMI ChartWork out BMI from weight in kg and height in feet and inches, see the Asian cut-off of 23, a height-weight chart, and how BMI works for kids.Calculators · 23 Oct 2026Car Loan EMI Calculator: Car, Bike & Personal Loan EMI ExamplesCar, bike and personal loan EMI with worked rupee examples, why a flat rate costs far more than it sounds, and how no-cost EMI really works.Calculators · 23 Oct 2026GST Calculation Explained: Inclusive vs Exclusive, CGST, SGST, IGSTAdd or remove GST with two simple formulas. Worked rupee examples for inclusive and exclusive prices, plus when CGST+SGST or IGST applies.Calculators · 23 Oct 2026GST Formula in Excel: Add GST & Reverse GST CalculationExcel formulas to add GST, remove GST from an inclusive price (reverse GST) and split CGST/SGST, with 18%, 12% and 5% examples.Calculators · 23 Oct 2026Home Loan EMI Calculator: EMI for ₹20, 30 & 50 Lakh LoansHome loan EMI for ₹20 lakh, ₹30 lakh and ₹50 lakh at 15–30 years, a worked bank example, how tenure changes total interest, and ways to reduce EMI.Calculators · 23 Oct 2026How EMI Is Calculated: Formula, Worked Example & PrepaymentSee the EMI formula with a step-by-step rupee example, why early EMIs are mostly interest, and how tenure and prepayment change what you pay.Calculators · 23 Oct 2026How to Calculate Age in Excel from DOB (DATEDIF Formula)Calculate age in Excel and Google Sheets from date of birth with DATEDIF: years, or years, months and days, today or as on any date.Calculators · 23 Oct 2026How to Calculate Discount Percentage (Formula & Examples)Discount % = (MRP − sale price) ÷ MRP × 100. Worked examples, why 50% + 20% off is 60% not 70%, buy 1 get 1 as a %, and the Excel formula.Calculators · 23 Oct 2026How to Calculate Percentage Increase & Decrease (Formula)Percent change = (new − old) ÷ old × 100. Worked examples for salary hike %, price drops and reverse percentages, plus the Excel formula.Calculators · 23 Oct 2026How to Calculate Percentage of Marks & Convert CGPA to PercentageMarks obtained ÷ total marks × 100, with worked examples. Plus how CGPA to percentage works, why rules differ by board, and CBSE's 9.5 factor.