2k predictor
Estimate your 2k time from a longer piece using Paul's Law (–5 s per 500m for every doubling of distance). This is a rough guide only — upload the real 2k for an exact figure.
Source piece
Predicted 2k 1:38.4 /500m · 6m 34s
Caveat: this assumes an aerobic longer piece rowed at a steady pace. Cold-start, sprint intervals, or extremely long pieces will skew the estimate.