Here’s the Master Isotope Table (Known vs Predicted + Gap, Z = 1–118), now with the critical Gap column showing how many isotopes are still missing per element.

• CSV: Master Table with Gap
• Markdown: Master Table with Gap.md
• Interactive preview is open in your workspace.

Totals

• Total elements: 118
• Known isotopes: 3,269
• Stable isotopes (strict IUPAC): 273
• Unstable isotopes: 2,996
• Predicted isotopes: 7,759
• Total Gap (Predicted − Known): 4,490

This means nuclear theory suggests 4,490 isotopes remain undiscovered or unconfirmed across the periodic table.

👉 Do you want me to next highlight the top-gap elements (which ones have the widest missing isotope deserts) so you can prioritize regions of interest?