OpenTools

⏲️ 555 Timer Calculator Compute frequency, period, and duty cycle for 555 astable and monostable circuits. 🔋 Battery Life Estimator Estimate battery life from capacity (mAh), average current, and optional duty cycling. 💡 LED Series Resistor Find the series resistor value and power rating for an LED from supply voltage, forward voltage, and current. ⚡ Ohm's Law Calculator Solve for voltage, current, resistance, or power — enter any two known values. 📐 Op-Amp Gain Calculator Select resistors for inverting or non-inverting op-amp configurations from a target gain. 📏 PCB Trace Width (IPC-2221) Calculate minimum PCB trace width for a given current and temperature rise per IPC-2221. 〰️ RC / RL / LC Filter Compute cutoff frequency, time constant, impedance, and Q for passive filters. 🎨 Resistor Color Code Decode 4, 5, or 6-band resistor color codes to value and tolerance, or encode a value to bands. 🔌 Voltage Divider Calculate output voltage, or find resistor values for a desired ratio. 🌉 Wheatstone Bridge Calculate bridge output voltage and balance conditions for Wheatstone bridge circuits.

📈 ADC Sampling Time Calculator Conversion time and max sample rate from ADC clock, resolution, and sampling cycles. 🔌 Baud Rate / UART Register Calculator USART BRR (STM32, over-sampling 8/16) and UBRR (AVR) register values with actual baud error %. 🚌 CAN Bit Timing Calculator Solve BRP, TSEG1, TSEG2 and SJW for a target CAN bitrate and sample point. 🌳 Clock Tree / PLL Calculator Solve PLL M/N/P/Q dividers for a target SYSCLK (and 48 MHz USB) from an input oscillator. ✅ CRC Calculator CRC-8/16/32 with configurable poly, init, refin/refout and xorout, computed live from text or hex bytes. 🔢 Fixed-Point (Q-format) Converter Convert float ↔ Qm.n fixed-point, with range, resolution, hex and binary raw value. ⏲️ I2C Timing Calculator Approximate STM32 I2C TIMINGR fields (PRESC/SCLL/SCLH/SCLDEL/SDADEL) for Standard/Fast/Fast+ modes. 🚦 NVIC Priority Calculator Preempt / subpriority split from PRIGROUP, for Cortex-M NVIC interrupt priorities. 📊 PWM Calculator Frequency, duty and resolution (bits) trade-offs for timer-generated PWM from a clock. 🔁 SPI Baud Prescaler Closest achievable SPI clock from a peripheral clock and prescaler, for STM32 and AVR. ⏱️ STM32 Timer Calculator Find PSC / ARR (and CCR) register values to hit a target timer frequency or period.

🔤 ASCII / Unicode Table Searchable ASCII table with dec/hex/oct/binary, escapes and Unicode code point lookup. 🔢 Base Converter Convert between binary, octal, decimal and hex with bit-width and two's-complement view. 🧬 Base64 Encoder / Decoder Encode text to Base64 or decode it back, with URL-safe alphabet, padding and line-wrap options. 🧮 Bit Manipulator Toggle bits visually, apply masks, shifts and rotations, and swap endianness. 🔐 Hex / Bytes / Base64 Encode and decode between UTF-8 text, hex bytes and Base64. 🔬 IEEE-754 Float Inspector Convert between floats and their bit patterns; inspect sign, exponent and mantissa.

🔤 Case Converter Convert text between camelCase, snake_case, kebab-case, Title Case, and more. 🧾 JSON Formatter / Validator Pretty-print, minify, and validate JSON with error location. 📋 Line Sort / Dedupe Tool Sort, unique, shuffle, reverse lines in a text block. 📜 Lorem Ipsum Generator Words, sentences, or paragraphs, with a custom starting phrase. 📝 Markdown Previewer Live-render Markdown to HTML side-by-side. 🧪 Regex Tester Live match highlighting, capture groups, and replace preview. 🔗 Slug Generator URL-safe slugs from arbitrary text, with transliteration. 🪢 String Escape / Unescape JSON, URL, and HTML entity escaping. 🔀 Text Diff Checker Line and word diff with add/remove highlighting. 🩹 Text Repair Studio Auto-fix mojibake / garbled text caused by wrong character encodings. 📊 Word & Character Counter Words, characters, sentences, paragraphs, and estimated reading time.

🕒 CRON Expression Calculator Parse a 5-field cron expression into a plain-English schedule and preview upcoming run times. 🔁 Ultra Unit Converter Convert length, mass, temperature, data rate, data size, frequency, and pressure — live, both directions.