Diagnostic & Reference Tools
Browser-based tools built for actual field work. No sign-up, no login, no nonsense. Bookmark the ones you use.
OBD2 Code Lookup
Search 200+ OBD2 fault codes by code number. Get plain-English explanations, common causes, and recommended fixes — plus links to relevant repair articles.
PC Upgrade Path Finder
Type in your laptop or desktop model and get exact upgrade recommendations — RAM, SSD, and Wi-Fi card — with compatibility notes and current pricing.
IP Subnet Calculator
Enter an IP address and CIDR notation or subnet mask. Get network address, broadcast address, usable host range, and host count instantly.
Wire Gauge Calculator
Input amperage, wire run distance, and voltage (12V / 24V / 120V / 240V). Get recommended AWG, voltage drop percentage, and safety warnings.
Barcode Identifier
Paste or type a barcode value and identify its symbology: Code 128, Code 39, UPC-A, EAN-13, QR, DataMatrix, and more. Useful for scanner configuration work.
4-20mA Current Loop Calculator
Convert a 4-20mA, 0-10V, or 1-5V process signal to engineering units (PSI, °C, %) and back. Get % of span and NAMUR NE43 fault flags for troubleshooting.
RTD Pt100 / Pt1000 Calculator
Convert RTD resistance to temperature and back for Pt100 and Pt1000 sensors, using the IEC 60751 Callendar-Van Dusen equation. °C, °F, and out-of-range checks.
PoE Power Budget Calculator
Add your access points, cameras, and phones and check total draw against a switch’s PoE power budget. Standard 802.3af/at/bt wattages with headroom warnings.
Modbus Register Decoder
Decode Modbus holding registers into int16, uint16, int32, uint32, and float32 across all four byte/word orders (ABCD, CDAB, BADC, DCBA).
Motor FLA & VFD Sizing Calculator
Full-load current from HP or kW, voltage, phase, power factor, and efficiency — plus a VFD output-current sizing hint. Single-phase, three-phase, and DC.
UPS Sizing & Runtime Calculator
Size a UPS from your load in watts with proper headroom, or estimate battery runtime from Ah and voltage — with honest derating for real-world losses.
Tire Size Comparison Calculator
Compare two tire sizes for the change in overall diameter, sidewall, circumference, and speedometer error — with a ±3% safe-swap warning.
Fuel Trim Interpreter
Enter STFT and LTFT and get a plain-English diagnosis — lean vs rich, vacuum leak vs fuel delivery — using the idle-vs-cruise pattern.
PSU Wattage Calculator
Estimate your PC’s power draw from its components and get a recommended power-supply wattage sized for efficiency and GPU transients.
RAID Capacity Calculator
Usable capacity, fault tolerance, and efficiency for RAID 0, 1, 5, 6, 10, and JBOD from your drive count and size.
IP Camera / NVR Storage Calculator
Estimate hard-drive storage for a security-camera system from camera count, resolution, frame rate, recording mode, and retention days.
Password Strength & Entropy Calculator
Check a password’s entropy in bits and crack time across realistic attack scenarios. Runs entirely in your browser — nothing is sent anywhere.
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If there's a reference tool you wish existed — something you'd actually use in the field — let me know. I build these because I use them myself.
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