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Engineering Made Easy

Simplify your workflow with powerful conversion, encoding, and calculation tools — all in one place, free and instant.

Popular Tools

Visualize 3D rotations from quaternion, Euler (intrinsic or extrinsic), axis-angle, or a 3×3 matrix. Interactive axes viewer with Unity YXZ, ROS ZYX, and Three.js XYZ orders.

Robot Arm FK/IK/Jacobian Calculator

Robot arm kinematics for learning & practice: FK/IK, DH tables, dedicated Jacobian tab with 6×N matrix, velocity mapping ẋ=J·q̇, manipulability index, SVD, singularity detection—aligned with cobots, industrial robots, humanoid arms, and AI robotics workflows. Robot programming friendly (CSV export). 2–6 DOF, SCARA, UR/KUKA-style presets, 3D visualization. Runs in your browser.

Endian Converter

Free online endian converter and byte swap calculator. Convert big endian to little endian with memory layout visualization, C bswap code generator, IEEE 754 float byte order, and htonl/ntohl reference for embedded and network developers

CRC Calculator

Calculate CRC checksums with 100+ algorithms. Supports ASCII, HEX, Binary, and file input (up to 10 MB) for data integrity verification.

Drone Calculator

Calculate drone thrust, TWR, hover throttle, flight time, and battery C-rating safety. Compare up to 4 motor/battery/propeller configurations side by side.

CRC Lookup Table

Browse CRC parameters and generate 256-entry lookup tables for 100+ CRC algorithms

Security & Hash

CRC Calculator

Calculate CRC checksums with 100+ algorithms. Supports ASCII, HEX, Binary, and file input (up to 10 MB) for data integrity verification.

CRC Lookup Table

Browse CRC parameters and generate 256-entry lookup tables for 100+ CRC algorithms

File Hash Calculator

Compute cryptographic hashes for files and text in your browser: MD5, SHA-1, SHA-256, SHA-384, SHA-512, SHA3, Blake2, and more. Drag-and-drop files, hex/base64 output, side-by-side comparison. Nothing uploaded—runs locally with Web Crypto.

HMAC Generator

Compute HMAC signatures and cryptographic hashes for text input. HMAC-MD5, HMAC-SHA1, HMAC-SHA256, HMAC-SHA384, HMAC-SHA512, HMAC-SHA3, HMAC-RIPEMD, HMAC-Whirlpool, and more. Hash text with MD5, SHA-1, SHA-2, SHA-3, Keccak, RIPEMD, SM3, Tiger. Hex/Base64 output, UTF-8/Hex input encoding. Runs locally.

JWT Encoder & Decoder

Decode JWT header and payload, verify HS256/HS384/HS512 HMAC or RS256/ES256 signatures with a secret, public key PEM, or certificate, and inspect exp/iat/nbf/iss/sub/aud. Encode HMAC JWTs from JSON. Convert RSA and P-256 public keys or certs between PEM and JWK/JWKS, inspect kty/n/e/crv/x/y, RFC 7638 thumbprint, kid matching, and x5c certificate summary—all in the browser.

TLS Certificate Analyzer

Decode PEM or DER X.509 certificates in the browser: subject/issuer, validity, SAN, key usage, fingerprints, and chain relationships—useful for HTTPS debugging and DevOps. No upload to a backend.

TOTP Generator

Generate RFC 6238 TOTP codes from a Base32 secret: SHA-1/SHA-256/SHA-512, 15/30/60s steps, 6 or 8 digits. otpauth:// QR for authenticator apps with SVG download, verify with time drift tolerance, always-visible HMAC debug, click-to-copy. Client-side only.

Text & Encoding

ASCII Converter

Convert text to ASCII codes and back: decimal, hex, binary, octal, U+xxxx, and C escape. Interactive ASCII table with control-character notes and character breakdown — useful next to CRC and UART debugging. Runs locally in your browser.

Base32 Encoder/Decoder

Encode and decode Base32 data for TOTP, 2FA secrets, and human-readable encoding

Base64 Encoder/Decoder

Encode and decode Base64 data with support for files and URLs

CSV / TSV Viewer & Converter

Parse CSV and TSV in the browser: delimiter and header auto-detect, spreadsheet-style grid with sort, filter, and dedupe. Export to JSON, JSONL, Markdown tables, SQL INSERT, TSV, or CSV. UTF-8 default with UTF-16 Excel support. Import JSON arrays and JSONL. No upload.

Format Converter

Convert between YAML, JSON, TOML, and HCL (Terraform) for Docker Compose, Kubernetes, CI/CD, and IaC. Validate syntax with line-number errors, preserve structure where possible—no upload.

HTML Entity Converter

Encode and decode HTML entities with named, decimal, hexadecimal, and mixed styles; selective modes for essential, extended, or Unicode characters; interactive entity reference. Client-side only.

JSON Formatter

Format and validate JSON with pretty print, JSONPath queries ($..key), JSON Schema validation, Tree View, Table View, YAML export, and minify—runs locally in your browser.

Markdown Editor

Live Markdown preview with GFM, YAML front matter preview, Mermaid diagrams, tables, task lists, footnotes, TOC, and HTML export. Ideal for README and static-site docs—runs in your browser.

Regex Tester

Test regular expressions with pattern library presets (email, URL, ISO date, UUID, IPv4), live highlighting, capture groups, case-insensitive and multiline flags, and find-and-replace. fancy-regex in WebAssembly—private, no server upload.

Text Case Converter

Convert naming conventions: camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, SCREAMING_SNAKE_CASE, title/lower/upper. Unicode-aware—CJK, Cyrillic, and other scripts preserved when mixed with English identifiers. Batch mode, runs locally.

Text Diff Comparator

Compare two texts or code snippets with side-by-side, inline, and unified diff views. Spot changes for code review, config drift, and documentation—processed locally in your browser.

Universal Text Codec

Encode or decode text in 20+ formats simultaneously: Base16, Base32, Base36, Base45 (RFC 9285), Base58 (Bitcoin/IPFS), Base62, Base64, Base64url, Base85 (Ascii85 & z85), Base91, URL percent-encoding, HTML entities, Unicode escapes (JS/Python), ROT13, Punycode, and more. Auto-detects encoding. All processing runs locally in your browser.

XML Formatter & Viewer

Format, minify, and validate XML with formatted output and an interactive tree view. Highlight nodes with XPath, search elements, sort attributes, and copy results—all in your browser.

Mathematical

3D Rotation Calculator

Free 3D rotation calculator. Multiply quaternions and compose Euler, axis-angle, and rotation-matrix chains — see the compound result in all four formats with live 3D visualization. Runs locally in your browser.

3D Rotation Converter

Convert a single rotation between quaternion, Euler angles, axis-angle, and 3×3 rotation matrix. Match Unity YXZ, ROS ZYX, and Three.js XYZ with multiple output panels. Runs locally in your browser.

3D Rotation Visualizer

Visualize 3D rotations from quaternion, Euler (intrinsic or extrinsic), axis-angle, or a 3×3 matrix. Interactive axes viewer with Unity YXZ, ROS ZYX, and Three.js XYZ orders.

Binary & Bitwise Calculator

Perform AND, OR, XOR, NOT, NAND, NOR, XNOR, bit shift, and bit rotate operations on 8, 16, 32, or 64-bit integers. Input in decimal, hex (0x), binary (0b), or octal (0o). Results shown as signed/unsigned decimal, hex, octal, and binary with color-coded bit visualization and popcount stats. Runs locally in your browser.

Endian Converter

IEEE 754 Converter

Convert decimal floats to IEEE 754 hex and binary bit patterns for 32-bit float and 64-bit double. Paste a firmware register dump, see sign/exponent/mantissa, and catch NaN/Inf. Pair with the Endian Converter for byte-swapped dumps.

Number Base Converter

Convert numbers between binary, decimal, hexadecimal, and octal with precision

Unit Converter

Convert metric and imperial units for length, mass, temperature, pressure, speed, torque (N·m, ft·lb, kgf·cm), flow rate (L/min, GPM), area, volume, data storage, time, energy, and more. Runs locally in your browser.

Engineering

Aerospace Calculator

Calculate orbital parameters from Keplerian or Cartesian inputs, estimate Hohmann transfer delta-v, and visualize 2D orbits. Includes ISA standard atmosphere (0-86 km) with temperature, pressure, density, speed of sound, Mach number, dynamic pressure, and drone thrust correction.

Bezier Curve Editor

Interactive cubic Bezier curve editor with real-time animation preview, 35 easing presets, side-by-side comparison, and code export for CSS, Unity C#, C++, and JavaScript.

Bit Mask Calculator

Define a register struct (name, start bit, width) and see the bitfield layout with C #define masks and a bitfield union. Also click bits on an 8/16/32/64-bit grid and apply SET, CLEAR, TOGGLE, or READ. For firmware and GPIO registers.

CAN Frame Analyzer

Analyze Classic CAN and CAN FD frames online. Parse Standard (11-bit) and Extended (29-bit) CAN IDs, validate DLC/data length, compute CRC-15/CRC-17/CRC-21, visualize bit layout, and decode DBC SG_ signals with Intel/Motorola byte order. Includes engine RPM, steering angle, and battery SOC presets.

Coordinate Frame Converter

Convert vectors and attitudes between NED, ENU, and Body coordinate frames. Visualize frame axes, apply roll/pitch/yaw DCM rotation, and understand frame relationships used in drone, robot, and navigation systems.

Drone Calculator

Calculate drone thrust, TWR, hover throttle, flight time, and battery C-rating safety. Compare up to 4 motor/battery/propeller configurations side by side.

Hex File Inspector

Inspect binary dumps in the browser: offset, hex, and ASCII columns with virtual scroll up to 10 MB. Paste hex in any common format (0x, \x, x-prefix, raw pairs, xxd / hexdump -C) or upload a file. Search hex or text, go to offset, choose dump output style (0x48, x48, 48, \x48), and edit bytes — overwrite, insert with hex value, delete, or download. Define struct overlays with CSV import/export; each field is color-coded in the dump with per-field LE/BE decoding (u8–u64, f32/f64, char[n]). Your last struct is restored from browser storage. No upload.

I2C Calculator

Interactive 7-bit I2C address map (0x00–0x7F) with reserved addresses highlighted, plus SCL timing (t_HIGH, t_LOW) and AVR TWBR register calculation for Standard, Fast, Fast-plus, and High-speed modes. Runs in your browser.

IP / Subnet Calculator

Calculate subnet information from CIDR notation, IP + prefix, or IP + mask. Shows network address, broadcast, first/last host, host count, wildcard mask, IP class, and color-coded binary layout. For DevOps, network engineers, and embedded systems.

LLM Token Calculator

Count prompt tokens in the browser before you hit the API. Compare GPT-4o, Claude, and Gemini context windows, reserve output tokens, and estimate input/output cost. tiktoken-based where the model encoding is known.

Logic Gate & Boolean Algebra

Analyze Boolean expressions in the browser: 64-row truth table (Copy CSV), Quine-McCluskey SOP/POS, Karnaugh map (2–4 vars), De Morgan rewrite, and IEEE gate schematics in four modes — As entered, Minimized SOP, Minimized POS, De Morgan — with PNG download. Click-to-copy SOP/POS/De Morgan. Operator insert buttons, categorized examples, NAND/NOR/XNOR support. Up to 6 variables. No upload.

PID Controller Calculator

Simulate PID controller step response for a first-order plant. Compute rise time, settling time, overshoot, and steady-state error. Includes Ziegler-Nichols tuning reference table. Runs in your browser.

PWM & Servo Calculator

Calculate PWM period, duty cycle, high/low time, servo angle-to-pulse-width mapping, and ESC throttle position. Supports standard (1000–2000 µs) and wide-range (500–2500 µs) servos. Runs in your browser.

Resistor Color Code

Decode resistor color bands to resistance values or encode a resistance value into color bands. Supports 4, 5, and 6-band resistors with tolerance and temperature coefficient. Free online resistor calculator.

Robot Arm FK/IK/Jacobian Calculator

SPI Calculator

Calculate SPI clock frequency from MCU clock and divider, transfer time, throughput, and bit/word periods. Browse all 8 clock dividers in a single table with speed class indicators. Supports SPI Mode 0–3 (CPOL/CPHA), MSB/LSB first, and word sizes of 8/16/32 bits. Runs in your browser.

UART Calculator

Calculate UART frame timing (bit period, frame duration, throughput) and baud rate error (UBRR register value, actual vs target baud) for 22 standard baud rates across 24 MCU clock presets. Supports 8×/16× oversampling modes. Runs in your browser.

Time & Date

Cron Expression Parser

Understand what a cron expression is, compare cron vs quartz, and parse Linux (5-field) or Quartz/Spring (6-7 field) cron job expressions. Generate human-readable cron schedules and next N execution times in any IANA timezone with presets and an expression builder.

Elapsed Time Calculator

Calculate elapsed duration between two datetimes in years, months, days, hours, minutes, seconds, and ISO 8601. Count business days with custom working weekdays, fixed date exclusions (YYYY-MM-DD, MM-DD), and recurring monthly rules (e.g. first Wednesday). Copy all formats as CSV. Runs locally in your browser.

Log Timestamp Sorter

Paste log lines, auto-detect ISO-8601, Unix epoch, RFC 2822, Apache/Nginx, syslog, Java/Python, Go, and HAProxy timestamps, normalize to UTC, sort chronologically, and export. Great for debugging distributed systems—client-side only.

Time Calculator

Paste two Unix epoch timestamps (seconds or milliseconds) and get the difference. Also add/subtract hours from a date, compare two datetimes, and calculate work hours with break deduction. DST-aware, runs in your browser.

Unix Timestamp Converter

Convert Unix epoch seconds to readable dates and back. ISO 8601 input & output, up to 10 multi-timezone outputs with inline settings, recent timezone chips, 7 date formats, 400+ IANA timezones, DST-aware. Runs locally in your browser.

Generators

Mock Data Generator

Free online mock data generator. Build a custom field schema and generate up to 1,000 rows of realistic fake data in JSON, CSV, or SQL INSERT format. 20 field types: Auto Increment, UUID, Name, Username, Email, Phone, Integer, Float, Boolean, Timestamp, Date, URL, IPv4, IPv6, MAC Address, Hex Color, Lorem Text, Country, Enum, Custom Fixed. Name and Phone in 12 languages. Lorem Ipsum generator in 13 languages. All processing runs locally — no data sent to any server.

Password Generator

Create strong passwords and tokens with adjustable length, character sets (upper, lower, digits, symbols), exclude ambiguous characters, and optional pronounceable or passphrase modes—generated locally in your browser.

QR Code & Barcode

Generate QR codes (URL, WiFi, vCard, email, phone, SMS, GS1 Digital Link) with optional center logo and multi-QR batch sheets, 1D barcodes (EAN-13, EAN-8, UPC-A, CODE128, GS1-128, CODE39, CODE93, ITF, Codabar, Code11) with human-readable digits, and ECC200 / GS1 Data Matrix. Decode QR, barcode, or Data Matrix from PNG, JPEG, WebP, GIF, BMP, SVG upload, or a live camera scan that stops when a symbol is read. Custom colors, Reed–Solomon L–H, SVG and PNG download. Runs locally in WebAssembly—nothing is uploaded.

UUID Generator

Generate UUID v1/v3/v4/v5/v7 (draft), URL-safe NanoIDs with custom alphabet and length, and 26-character time-sortable ULIDs in your browser. RFC 4122 compliant, copy to clipboard, no server—ideal for database keys and APIs.

Web Development

Color Converter

Free online color converter: HEX, RGB, HSL, HSV, HWB, CMYK, and NCol with bidirectional editing. Harmony palettes (complementary, analogous, triadic, square/tetradic, Tailwind CSS scale) plus CSS variables and Tailwind config copy. WCAG 2.1 AA/AAA contrast for foreground vs background (normal and large text), preview, and vs white/black. Color history, one-click copy—runs in your browser.

CSS Toolbox

Free online CSS generator and toolbox. Create box-shadow, text-shadow, border-radius, CSS filter, linear/radial/conic gradient, Flexbox, and CSS Grid with live preview and one-click copy. Minify or beautify CSS. Convert px to rem, em, pt, vw, vh, and percent. Runs locally in your browser — no upload.

cURL & API Converter

Build HTTP requests and generate code in 8 languages (cURL, Python requests/httpx, JS fetch/axios, Go, PHP, Rust reqwest). Convert Python/JS code back to cURL. Parse Cookie/Set-Cookie headers with security warnings. Analyze HTTP security headers (HSTS, CSP, X-Frame-Options) with A-F grading. All local, nothing sent to server.

HTTP Code Generator

Build HTTP/GraphQL requests visually: GraphQL query & mutation templates, OAuth2 Bearer preset, headers, query, JSON body, auth. Export cURL, fetch, Axios, Python requests, Go, Rust, Java.

URL Encoder/Decoder

Percent-encode or decode URLs, parse scheme/host/path/query components, and edit query parameters in a table with encoding toggle. UTF-8 support; runs in your browser.

Image

Image Converter, EXIF Viewer & Palette Extractor

Free online image toolkit: convert between PNG, JPEG, WebP with resize, inspect and strip EXIF metadata (GPS, camera info), extract dominant color palettes (K-means), compress to target KB, crop with aspect-ratio presets, remove background color (transparency), and apply blur. Compare two images with a before/after slider, side-by-side view, and pixel-diff heatmap with threshold. All processing runs locally in your browser — no upload, no server.