GPSTime vs TrueOffset

GPSTime is a time conversion tool designed for researchers, students, and GPS/GNSS professionals. Time conversion is a frequent challenge in GNSS work—whether parsing broadcast ephemerides, handling IGS product names, or aligning observation data. GPSTime streamlines this process by providing accurate conversions between GPS Time and UTC, with full support for leap seconds. The app supports a wide range of commonly used formats, including: • GPS Week + Time of Week (TOW) • GPS Week + Day of Week (DOW) • Gregorian calendar (YYYY-MM-DD HH:MM:SS) • Year + Day of Year (DOY) • Modified Julian Date (MJD) Using historical leap-second data, GPSTime ensures correct handling of the GPS–UTC offset for both past and present times. GPSTime is also capable of saving your conversion history (up to 200 logs in the History tab) and lets you configure default conversion scenarios to match your most frequently used time system and format. With a clean interface and multiple input/output options, GPSTime is an essential companion for GNSS research, education, and precise timekeeping tasks.

TrueOffset is a precision time utility for comparing time sources and measuring clock offset with clarity and confidence. Compare multiple Network Time Protocol (NTP) servers, visualize the difference between them, and see how your device's clock aligns with selected references. A clean, instrument-style interface presents time as a measurement—focused on accuracy, not decoration. FOUR CLOCK FACES - 12-Hour Classic — Traditional analog display - 24-Hour Scientific — Full day on one dial - NTP Offset — Dual second hands show device vs. true time - Digital — Large display with millisecond precision UTC & TAI TIME SCALES Display Coordinated Universal Time (UTC) and International Atomic Time (TAI) alongside your local time. UTC and TAI feature authentic deadbeat second hands that step crisply to each second, visually distinct from the smooth-sweep local time. TAI runs 37 leap seconds ahead of UTC—see both atomic time scales at a glance. PRECISION VISUALIZATION The NTP Offset view displays two second hands: your device clock (gray) and true NTP time (green). The offset magnifier shows drift on a ±10ms scale, so you can see sub-millisecond accuracy at a glance. DUAL-STACK COMPARISON A feature no other NTP app offers: compare IPv4 and IPv6 paths to the same server. Detect DNS misconfigurations, identify when address families route to different servers, and verify your network is delivering consistent time on both stacks. FLEXIBLE TIME SOURCES Compare against Apple, Google, Cloudflare, NIST, US Naval Observatory, global NTP pools, or add your own servers. Set any source as your reference and track offsets across all configured servers. QUALITY ANALYTICS Eight swipeable chart pages reveal the character of your time sources: - Dashboard — Sparkline overview of all servers - Offset History — Track drift over time - Histogram — Offset distribution analysis - Box Plot — Compare consistency across servers - RTT Scatter — Correlate latency with offset - Clock Sources — Decode reference clocks (GPS, PPS, Rubidium, Cesium) - Dual-Stack — IPv4 vs IPv6 path comparison - Rankings — Servers scored by jitter and round-trip time TrueOffset is designed for users who care about how accurate their time really is—and want to see the difference, not just trust it. --- In appreciation of Emerald Sequoia's Emerald Time.