All Tools

Free tools for the jobs that keep coming up with online forms and everyday work: shrinking a PDF to a KB limit, resizing a photo or signature, making a QR code or checking a caption. Search by what you need to do, or browse the groups below.

Runs in your browser — nothing is uploaded or stored on a server.

Lab tools

QC CalculatorLevey-Jennings charts with the full Westgard rule set, dated logs and printed reports Dilution CalculatorBuffers, serial dilutions and molarity for the bench BioLinguist assistantAsk, talk or drop a file — it works every tool on this site RoastBotThe assistant with no bedside manner

Everyday tools

Health CalculatorBMI, BMR, calories and macros for your goal Image CompressorShrink, crop and convert JPG, PNG, WebP PDF ToolsMerge, split, sign, compress, convert QR Code GeneratorLinks, Wi-Fi, vCard, UPI — with logo and colours Password GeneratorStrong passwords, passphrases, strength check Word CounterWords, characters, reading time — Hindi too

PDF tasks

Compress PDFAny quality, or an exact KB limit Compress PDF to 200 KBFor forms that cap uploads at 200 KB Compress PDF to 100 KBThe strictest form limit, handled JPG to PDFPhotos into one tidy PDF PDF to JPGEvery page as a sharp image Merge PDFSeveral PDFs into one, in order PDF to WordEditable text from any PDF

Photo and image tasks

Compress image to 20 KBSignatures and small photos for forms Compress image to 50 KBApplication photos under 50 KB Passport size photo3.5 × 4.5 cm, under 50 KB HEIC to JPGiPhone photos that open everywhere JPG to WebPFaster website images

QR code tasks

Wi-Fi QR codeGuests scan once and connect UPI QR codeScan & Pay card for your counter

Text tasks

Instagram caption counterStay inside the 2,200 limit

Which tool do I need?

Upload limits on government, exam and job portals cause most of the trouble. If a form rejects a document for being too large, start with Compress PDF; when the form names a number, the 200 KB and 100 KB pages are already set to it. Photo and signature boxes have their own, much smaller limits — use Compress image to 20 KB for signatures, Compress image to 50 KB for photos and Passport size photo when the form asks for 3.5 × 4.5 cm.

If you have photos of documents but the form wants a single PDF, JPG to PDF joins them in order, and Merge PDF does the same for PDFs. Going the other way, PDF to JPG turns pages into images and PDF to Word gets the text out so you can edit it. iPhone photos that won't open or upload are usually HEIC files, which HEIC to JPG converts.

For shops and homes, the UPI QR code page makes a Scan & Pay card for a counter, and the Wi-Fi QR code lets guests join your network without typing a password. Lab staff will find the QC calculator, with Levey-Jennings charts and Westgard rules, and the dilution calculator for buffers, serial dilutions and molarity.

How these tools work

Each tool is a web page that does its work inside your browser, on your own phone or computer. Files are not uploaded, there is no sign-up and no watermark, and once a page has loaded most tools carry on working even if the connection drops. You can also install masstree.in from the browser menu to keep the tools a tap away.

Questions

Are these tools really free?

Yes — no sign-up, no watermark and no limits. They run in your browser, so there is nothing to pay for on a server.

Are my files uploaded?

No. PDFs, photos and text are processed on your own device. Only the assistant's typed questions, voice clips and e-mail breach checks are sent to a server, and those are not kept. The site does keep a simple visit log of page, time, IP address and browser, with no cookies.

Can I use them on my phone?

Yes, every tool works in Android and iPhone browsers, and you can install masstree.in as an app from the browser menu.