ToolsKaro Blog
Practical guides on preparing photos & signatures for online forms, compressing images and PDFs to an exact size, converting formats and more.
How to Convert CSV to JSON (With Examples)
Have spreadsheet data but need JSON for your code or API? Here's how to convert CSV to JSON cleanly — headers as keys, quoted commas handled.
Image toolsWhat Is a JFIF File and How to Convert It to JPG or PNG
Downloaded an image that saved as .jfif and won't open where you need it? Here's what JFIF is and how to convert it to JPG or PNG in seconds.
CalculatorsMeters to Feet: How to Convert (Formula, Chart & Tool)
One meter is 3.28084 feet — here's the formula, a handy chart, and a free tool that also does cm, inches, miles, kg, and Celsius to Fahrenheit.
Image toolsHow to Convert Text to an Image (JPG or PNG) for Free
Need your words as a picture — a quote, a caption, an uneditable snippet? Here's how to turn text into a clean JPG or PNG in seconds.
CalculatorsDog Years to Human Years: How Old Is Your Dog Really?
The 'multiply by 7' rule is a myth. Here's how dog years really map to human years — and why a Chihuahua and a Great Dane age very differently.
Document toolsHow to Convert PowerPoint to Word (Free, No Software)
Need the wording of a deck in Word? Here's how to turn a PowerPoint into an editable .docx in seconds — free, private, and with no software to install.
Document toolsHow to Resize Photo and Signature for a PAN Card
Get your photo and signature for a PAN card application sized correctly the first time. Learn the exact dimensions, file sizes, and how to resize both online in minutes.
Image toolsHow to Resize a Photo for Your WhatsApp DP
WhatsApp crops and zooms every profile picture into a circle. Here is the ideal WhatsApp DP size and how to resize a photo so your face stays perfectly centred.
PDF toolsHow to Combine Bank Statements Into One PDF
A clear, step-by-step guide to merging several months of bank statements into one clean PDF, including how to unlock encrypted statements, fix the page order and shrink the file to fit an upload limit.
Image toolsHow to Combine Photos Into One Image (Free)
A simple, free way to combine photos into one image. Join pictures side by side, stack them, or build a quick grid with a browser photo joiner.
Image toolsHow to Resize an Image in CM at 300 DPI
A plain-English guide to resizing an image in cm at 300 DPI, with the pixel formula, why 300 DPI matters for printing, and the exact steps to do it.
PDF toolsHow to Resize a PDF to A4 Size (Free, No Upload)
A plain-English guide to resizing any PDF to A4 size right in your browser, why PDFs end up the wrong page size, and how to shrink the file afterwards.
Image toolsHow to Join Two Photos Into One Image Free (Side by Side or Stacked)
Want to put two pictures next to each other or make a quick collage? Here's how to join photos into one image for free, without uploading anything.
PDF toolsHow to Merge Two PDF Files Into One (Free, No Upload)
Need to join two PDFs into one? Here's the fastest free way to do it in your browser — and how to fix the page order and file size after.
Image toolsHow to Compress an Image to 100 KB Without Losing Quality
Need a photo under 100 KB? Here's how to hit that target while keeping it clear — the trick is what you do before you compress.
Developer toolsUUID v4 vs v1: Which UUID Version Should You Use?
v1 is built from a timestamp and MAC address; v4 is fully random. Here's which UUID version to use, and why v4 is the safe default.
Developer toolsSHA-256 vs MD5: Which Hash Should You Use?
MD5 is fast but broken; SHA-256 is the modern default. Here's the difference, in plain English, and which one to pick.
Developer toolsHow to Fix "Invalid JSON" Errors: 8 Common Causes
Trailing comma? Single quotes? Here are the 8 things that make JSON invalid — and the fastest way to find the exact line that's broken.
Image toolsHow to Compress an Image to 20 KB Without Blurring It
20 KB is tiny — but your photo doesn't have to look it. Here's how to hit 20 KB and stay sharp.
PDF toolsHow to Scan a Document With Your Phone and Save It as a PDF
No scanner? Your phone is one. Here's how to turn photos of documents into a single, upload-ready PDF.
Exam formsHow to Put Your Photo and Signature on One Image for an Exam Form
Form asking for your photo and signature as one image? Here's how to combine them cleanly and size it for upload.
Image toolsHow to Convert HEIC to JPG on Windows Without Installing Software
Got iPhone HEIC photos on your Windows PC that won't open? Convert them to JPG without installing anything.
Passport photoWhy Does My Passport Photo Keep Getting Rejected? Common Reasons & Fixes
Uploaded the same photo three times and it keeps getting rejected? Here are the real reasons — and the fix for each.
Image toolsHow to Increase Image Size in KB (For Minimum Size Limits)
Form rejecting your photo for being too small? Here's how to increase its file size to meet a minimum.
CareerHow to Make a Professional Email Signature for Gmail & Outlook
A clean email signature makes every message look credible. Here's how to build one and add it to Gmail or Outlook.
Image toolsImage DPI Explained: What 300 DPI Means and How to Change It
Forms ask for '300 DPI' — but what does that actually mean, and how do you set it? Here's the plain-English answer.
PDF toolsHow to Reduce PDF Size for Email Attachments
Email bouncing because your PDF is too big? Here's how to shrink it under the attachment limit.
Image toolsHow to Remove the Background from a Photo for Free
Cut out the background of any photo automatically — no design skills, no watermark, and nothing uploaded.
Passport photoHow to Make a Passport Size Photo at Home for Free
Skip the studio. Here's how to turn a normal photo into a proper passport size photo at home, for free.
CareerResume PDF Tips: Size, Format and Passing ATS Systems
A great resume gets rejected if the file is too big or unreadable by an ATS. Here's how to get the PDF right.
PDF toolsHow to Combine Multiple Images or Documents Into One PDF
Need to submit several pages as one file? Here's how to combine images and PDFs into a single document.
Exam formsPhoto & Signature Requirements for SSC, IBPS, UPSC & RRB Exams
Each commission has its own photo and signature rules — and bank exams need even more. Here's a quick reference.
Image toolsHEIC Files Explained: Why iPhone Photos Won't Open and How to Fix It
Sent an iPhone photo and the other person can't open it? It's a HEIC file. Here's what that means and how to fix it.
PDF toolsHow to Compress a PDF Below an Upload Limit (200 KB to 1 MB)
Portal won't accept your PDF because it's too big? Here's how to shrink it under the limit without making it unreadable.
Image toolsJPG vs PNG vs WebP vs HEIC: Which Image Format Should You Use?
JPG, PNG, WebP, HEIC — what's the difference, and which one should you actually use? Here's the simple answer.
Passport photoPassport Size Photo Dimensions: cm, Inches & Pixels (Full Guide)
What exactly is a 'passport size' photo? Here are the dimensions in cm, inches and pixels for India, the US and more.
Image toolsHow to Compress a Photo to 50 KB Without Losing Quality
50 KB is the most common photo limit on Indian forms. Here's how to hit it while keeping your photo clear.
Exam formsHow to Resize Your Photo and Signature for Government Exam Forms
Every government exam form rejects photos that are the wrong size. Here's how to hit the exact dimensions and KB they ask for — in two minutes, free.