Help
Quick answers for every tool. Can’t find yours? Write to us on the contact page.
General
Are my files uploaded?
No. Every tool works inside your browser. Photos, PDFs and the details you type never leave your device.
Is 123ToolBox free?
Yes. Every tool is free, with no sign-up and no watermark. Ads help keep it free.
Which browsers work?
Chrome, Edge, Firefox and Safari, on Android, iPhone, Windows and Mac. Keep your browser updated for best results.
The download does not start on my phone.
Allow downloads for this site when your browser asks, or long-press the result and choose Save. Some in-app browsers (Instagram, Facebook) block downloads: open the page in Chrome or Safari instead.
The tool is slow.
Very large photos and long PDFs take longer on older phones. Keep the page open on screen until it finishes.
Photo & signature
Resize photo to KB
How do I reduce photo size to 20 KB?
Choose your photo, tap 20 KB and tap Resize. The tool gives you a JPG just under 20 KB.
Is my photo uploaded anywhere?
No. The photo is processed inside your browser and never leaves your device.
Why is the result a little under 20 KB, not exactly 20 KB?
Forms reject files even one byte over the limit, so we always stay just under it.
The form says 20 KB to 50 KB. Which should I pick?
Pick 50 KB for the clearest photo. Pick 20 KB only when the form says “maximum 20 KB”.
Can I resize a PNG or screenshot?
Yes. JPG, PNG and WEBP photos work. The result is saved as JPG, which most forms accept.
Does it work on mobile?
Yes. It works in Chrome on Android and Safari on iPhone.
Signature resize
What size should a signature be for online forms?
Most forms ask for 10 KB to 20 KB. Check your form notice: it also gives width and height in pixels or centimetres.
How do I make the signature background white?
Keep “Clean background” on. It turns light grey and yellow paper to pure white and keeps the ink dark.
Can I use blue ink?
Yes. The ink colour is kept. Only the paper becomes white.
Is my signature uploaded?
No. It is processed on your device only.
My signature looks too small or cut off.
Take the photo close to the paper and crop it tight around your signature before choosing it.
Compress image
Will my photo lose quality?
At 70–80% quality the change is very hard to see, while the file becomes much smaller.
Can I compress many images at once?
Yes. Choose several photos together; each one is compressed separately.
What formats are supported?
JPG, PNG and WEBP. You can keep the format or save as JPG or WEBP.
Are my images uploaded?
No. Compression happens on your device.
I need an exact size like 50 KB.
Use Resize photo to KB, which hits an exact KB limit.
Image converter
How do I convert WEBP to JPG?
Choose the WEBP image, pick JPG and tap Convert.
What happens to transparent backgrounds?
They stay transparent in PNG and WEBP, and become white in JPG.
Can I convert HEIC iPhone photos?
Not yet in this tool. HEIC support is coming. Meanwhile, set your iPhone camera to “Most Compatible” to save JPG.
Is there a file limit?
No fixed limit. Very large photos may be slow on older phones.
Photo with name and date
How do I add name and date on a photo for an exam form?
Choose your photo, type your name and the photo date, pick the size and tap Make exam photo. The name and date appear in a white strip at the bottom.
Which date should I write?
The date the photo was taken. Many notices ask for a photo taken recently, so take a fresh one if yours is old.
What size should the photo be?
Use the size in your official notice. 3.5 × 4.5 cm is the usual passport size; some forms give pixels such as 200 × 230.
Is my photo uploaded?
No. The photo is made on your device and never leaves it.
Passport size photo
What is the passport size photo size in India?
35 × 45 mm (3.5 × 4.5 cm). That is about 413 × 531 pixels at 300 dpi.
How many passport photos fit on a 4×6 paper?
8 photos of 35 × 45 mm, in 2 rows of 4.
How many fit on an A4 sheet?
Up to 30 photos of 35 × 45 mm.
How do I print them the right size?
Print the JPG or PDF at 100% or “actual size”. Do not choose “fit to page”.
Does it remove the background?
Not yet. Stand in front of a plain white or light wall when you take the photo.
Crop image
How do I crop a photo in a circle?
Choose Circle (DP), place the circle and tap Crop. It is saved as a PNG with a clear background.
How do I crop a photo to passport size?
Choose Passport 35×45, place the box over your face and crop. Use Resize photo to KB if the form also has a KB limit.
Does cropping reduce quality?
No. The kept part keeps its original pixels unless you type a smaller width.
Is my photo uploaded?
No. It is cropped on your device.
HEIC to JPG
How do I convert HEIC to JPG on Windows?
Open this page in Chrome or Edge, choose the HEIC files and download the JPGs. No software to install.
Can I convert many HEIC photos at once?
Yes. Choose them all together; each one is converted and you can download all.
Does it lose quality?
At Best or High quality the JPG looks the same as the original.
Are my photos uploaded?
No. They are converted on your device.
How do I stop my iPhone saving HEIC?
On the iPhone go to Settings → Camera → Formats and choose Most Compatible.
JPG to PDF
How do I convert multiple JPGs into one PDF?
Choose all the photos together, set the order and tap Create PDF. You get one PDF with one photo per page.
Can I change the page order?
Yes. Use the up and down arrows next to each photo.
Is there a watermark?
No. The PDF has only your photos.
My PDF is too big for the form.
Compress the photos first with Compress image, then make the PDF.
Are my photos uploaded?
No. The PDF is made on your device.
Merge PDF
How do I combine PDF files into one?
Choose all the PDFs, set the order and tap Merge PDF.
Is there a limit on files?
No fixed limit. Very large PDFs may be slow on older phones.
Can I merge password-protected PDFs?
Not yet. Remove the password first.
Are my files uploaded?
No. Merging happens on your device.
PDF to JPG
How do I convert a PDF to JPG on mobile?
Open this page in Chrome, choose the PDF and download the pages. No app needed.
Can I convert only one page?
Yes. All pages appear; download only the ones you need.
Is quality kept?
High quality makes sharp images good for printing. Normal makes smaller files for sharing.
Is my PDF uploaded?
No. The pages are drawn on your device.
Compress PDF to KB
How do I compress a PDF to 100 KB?
Choose the PDF, tap 100 KB and tap Compress. You get a PDF just under 100 KB.
Will the text still be readable?
Yes for most documents. If a PDF has many pages, very small sizes can blur it; then pick a bigger size or split the PDF first.
Can I copy text from the compressed PDF?
No. Pages are turned into images to make them small. Keep your original if you need to copy text.
Is my PDF uploaded?
No. It is compressed inside your browser and never leaves your device.
Why does it say “too small”?
Some PDFs have too many pages to fit in the size you picked. Choose a bigger size or remove pages with Split PDF.
Split PDF
How do I extract one page from a PDF?
Open the PDF, tap only that page and tap Save. You get a new PDF with just that page.
Can I save every page separately?
Yes. Choose “Every page → its own PDF”. Your phone may ask once to allow several downloads.
How do I type page ranges?
Use commas and dashes: 1-3, 5, 8- means pages 1 to 3, page 5 and page 8 to the end.
Is my PDF uploaded?
No. Splitting happens on your device.
Rotate PDF
How do I rotate only one page of a PDF?
Tap the ↻ button on that page until it is upright, then save.
Is the rotation saved permanently?
Yes. The new PDF opens the right way in every app.
Does rotating reduce quality?
No. Pages are only turned, not redrawn.
Is my PDF uploaded?
No. It is rotated on your device.
Add page numbers
How do I add page numbers to a PDF?
Choose the PDF, pick a position and style, and tap Add page numbers.
Can I start numbering from page 2?
Yes. Tick “Don’t number the first page” so the cover page has no number and page 2 shows 1.
Can I use “Page 1 of 10”?
Yes. Pick that style; the total is counted for you.
Is my PDF uploaded?
No. Numbers are added on your device.
PDF to text
How do I copy text from a PDF on mobile?
Choose the PDF here and tap Copy all text. Then paste it anywhere.
Why is no text found?
The PDF is probably a scan, which is a picture of text. It needs text recognition (OCR) instead.
Why does Hindi or Kannada text look strange?
Some PDFs use old non-Unicode fonts. Their letters cannot be read back correctly by any converter.
Is my PDF uploaded?
No. The text is read on your device.
QR & barcode
QR code generator
Do these QR codes expire?
No. The information is inside the QR code itself, so it works as long as the picture exists.
How do I make a UPI QR code for my shop?
Choose UPI, enter your UPI ID and shop name. Leave the amount empty so customers type their own.
How does the WiFi QR code work?
Guests scan it and their phone joins your WiFi without typing the password.
Can I change the colours?
Yes. Keep the code dark on a light background so all phones can read it.
Is this free for business use?
Yes. Print them on menus, cards and posters.
Should I test the QR code?
Always. Scan it with your phone camera before printing.
Barcode generator
Which barcode type should I use?
Code 128 for your own stock labels. EAN-13 for retail products sold in shops, using the number given to your product.
Where do I get an EAN-13 number?
Products sold through retailers need a number from GS1 India. For your own shelves, use Code 128 with any code.
Why does it say the number is not valid?
EAN and UPC need an exact count of digits and a correct check digit. Code 128 accepts almost anything.
Can I print these?
Yes. Download SVG for the sharpest print at any size.
Calculators
Age calculator
How do I calculate age as on a specific date?
Enter your date of birth and set “Age on” to the date in the notice.
How is the age counted?
Full years first, then full months, then the remaining days, the same way exam boards count.
Does it handle leap years?
Yes. 29 February birthdays are handled correctly.
Is my date of birth saved?
No. Nothing leaves your device.
EMI calculator
How is EMI calculated?
EMI = P × r × (1+r)^n ÷ ((1+r)^n − 1), where P is the loan, r the monthly rate and n the number of months.
Does a longer loan lower my EMI?
Yes, but you pay much more interest in total. The table shows the difference.
Is this the exact bank EMI?
It is very close. Banks may add processing fees or round differently.
Does it include insurance or fees?
No. Only the loan and interest.
Interest calculator
What does ₹2 per 100 interest mean?
For every ₹100 given, ₹2 interest is paid every month. That is 2% a month, or 24% a year. On ₹50,000 it is ₹1,000 every month.
How do I calculate interest from date to date?
Choose “Between two dates” and set the date the money was given and the date it is returned. The tool counts full months and the extra days.
How are the extra days counted?
A day is counted as 1/30 of a month, the way most private lenders count. 15 extra days is half a month of interest.
What is the difference between simple and compound interest?
Simple (sadharan) interest is counted only on the amount given. Compound (chakravarti) interest is added to the amount after each year, 6 months or month, so later interest is counted on the bigger amount.
How do I change ₹ per 100 into % per year?
Multiply by 12. ₹1 per 100 a month is 12% a year, ₹1.5 is 18%, ₹2 is 24% and ₹3 is 36%.
Are my numbers saved anywhere?
No. Everything is calculated on your phone and nothing is sent anywhere.
SIP calculator
How is SIP return calculated?
Each monthly payment grows at the monthly rate (yearly return ÷ 12) until the end. Value = P × ((1+i)^n − 1) ÷ i × (1+i), where P is the monthly amount, i the monthly rate and n the number of months.
What is a step-up SIP?
You raise your SIP by a fixed percent every year, for example 10%. It builds a much bigger amount than a flat SIP.
What return should I use?
Nobody can promise a return. Many people check with 10–12% for equity funds over long periods and lower for debt funds. Try a few rates.
SIP or lumpsum, which is better?
Lumpsum puts all money in at once; SIP spreads it over months and suits a monthly salary. Switch the tab to compare.
Is this investment advice?
No. It is a calculator for planning. Mutual fund investments are subject to market risks.
Percentage + CGPA
How do I calculate percentage of marks?
Divide the marks you got by the total marks and multiply by 100. 437 out of 500 is 437 ÷ 500 × 100 = 87.4%.
How do I convert CBSE CGPA to percentage?
Multiply the CGPA by 9.5. A CGPA of 8.4 is 79.8%.
What is the VTU CGPA to percentage formula?
VTU uses Percentage = (CGPA − 0.75) × 10. A CGPA of 8 is 72.5%. Check your marks card for the formula of your scheme.
How do I find percentage of 6 subjects?
Add the marks of all 6 subjects, add their maximum marks, then use Marks to %.
How do I calculate percentage increase?
Choose % increase / decrease and enter the old and new values. From 25,000 to 28,000 is a 12% increase.
GST calculator
How do I calculate GST on a price?
Multiply the price by the rate. 18% GST on ₹1,000 is ₹180, so the price with GST is ₹1,180.
How do I remove GST from a total (reverse GST)?
Divide the total by 1 + rate. For ₹1,180 at 18%: 1,180 ÷ 1.18 = ₹1,000 before GST, and ₹180 is the GST.
What are the GST rates now?
Since 22 September 2025 most goods and services are at 5% or 18%, with 40% for a few luxury and sin goods. Gold is 3%.
When is it CGST + SGST and when IGST?
Within the same state the GST is split half CGST and half SGST. To another state it is charged as IGST.
Typing & text
Word counter
How many words is a 2-minute speech?
About 250–300 words. People speak around 130–150 words a minute.
Does it count spaces as characters?
It shows both: characters with spaces and characters without spaces.
Does it work for Hindi and Kannada?
Yes. Words and letters in Hindi, Kannada and other Indian scripts are counted correctly, including joined letters.
Is my text saved or sent anywhere?
No. The text stays in your browser and disappears when you close the page.