Smart calculator — normal & scientific (runs in your browser)
How to use · examples · privacy
How it was solved
Keypad
Scientific keys
Encode, convert units, tune images on canvas, format JSON, view PDFs/DOCX, test regex, open Math lab or Advanced labs (CIDR, Luhn, WCAG contrast) — same tab, no uploads, no account.
Quick Ctrl + K to search like you mean it · ? for shortcuts · star tools in search · paste buttons where you edit text
One tap to open the right workspace and start quickly.
Tap a card — the tool opens in a quick popup over this list. Filter by category or search (count loads with the page).
… tools on one page — students, teachers, devs, café Wi‑Fi. Search or pick a category; each card nudges you toward related picks below.
Every standalone URL below uses the same local processing as the app — open in a new tab or share the link. Also see the full index.
Spaces optional in hex input.
Round-trip in your browser (js-yaml). Use the main JSON editor above after “YAML → JSON”.
Paste CSV — basic quoted-field support.
Uses browser CompressionStream (Chrome, Edge, Safari 16.4+).
Keypad
Scientific keys
Each row is a mini-solver: enter only the numbers you already have. If a shape needs two facts (e.g. circle: area and radius), fill one to get the other — or both to verify. If it needs three (rectangle: area, length, width), fill two to get the third. Letters and symbols are ignored in number boxes. Tap Calculate.
Open a row → pick direction → type one number (digits only). Tap Calculate.
Any two of A, ℓ, w finds the third. All three checks ℓ×w = A.
Any two of A, b, h — third is computed (b,h ≠ 0 when dividing).
Give A or r (or both to verify).
Any three of A, a, b, h determine the fourth (parallel sides a, b).
Any three of V, ℓ, w, h — fourth unknown (divide only if product of known edges ≠ 0).
Any two of V, r, h find the third (r,h ≥ 0).
V from r, or r from V (V ≥ 0).
Any two of V, r, h — third unknown.
Any two nonnegative sides find the third (c is longest when all known).
One page — many solvers: number theory, combinatorics, linear systems, complex numbers, 2×2 matrices & eigenvalues, 3D vectors, numeric derivative & integral of f(x), descriptive stats, binomial PMF, arithmetic/geometric sums, compound interest & loan EMI, deg↔rad. Curriculum-style topics through 2026; all evaluation runs in your browser.
A = [[a,b],[c,d]] · B = [[e,f],[g,h]]
x)Same functions as main calculator. Trig uses radians.
Compound A = P(1+r)ᵗ (r decimal/year). EMI: monthly rate = annual%/12/100.
Rendered with marked + DOMPurify (scripts/iframes stripped). For notes & READMEs.
Preview
PNG → JPEG (or stay PNG): open a photo, adjust, then JPEG for smaller files or PNG for lossless. Download runs in your browser — no upload to a server.
Click image to pick a pixel color (shown in Color tab).
Draw with mouse or finger. Export PNG or a one-page A4 PDF — processing stays in this browser. This is not a government PKI / DSC; it’s a bitmap for forms and PDFs.
Live preview
Open a file to preview in-browser: PDF pages, DOCX text extract, TXT/MD/JSON/XML editing, and safe HTML preview. Nothing is uploaded.
Supported: PDF, DOCX, TXT, MD, HTML, CSV, JSON, XML, YAML.
Image studio mein image par click karke bhi color yahan set hota hai.
Paste a JWT; header & payload decode locally. Signature is not cryptographically verified here.
Header
Payload
Signature (base64url · not verified)
Category · Text
Category · Codes & scans
High error correction for print; size matches scan distance.
Retail & logistics formats (JsBarcode). Values must match format rules.
Category · Passport & ID photos
Choose from global presets (always verify latest embassy/authority rules). Fine-tune framing with fit, zoom, and X/Y position before export. Output is an A4 printable grid and continues to additional pages when needed.
Use a clear face-forward photo, then adjust zoom and positioning to match requirements.
Category · Compress
Images: re-encode JPEG/WebP with quality. PDF: each page is rasterized and re-packed (can reduce scans a lot; text-only PDFs may not shrink much).
Max 40 pages per run (keeps tab responsive).
Enter address/prefix (e.g. 192.168.1.0/24). All math runs locally.
Card numbers, IMEI — digits only (spaces OK). Does not contact issuers.
Rough bits of entropy from length × character classes — educational, not a bank audit.
Encode / decode for TOTP backup codes & binary-safe text.
Foreground vs background — relative luminance & large/normal text AA/AAA.