Answer: on balance, Messi is better, and Ronaldo has a reasonable case. "Better" has no agreed definition, so this is a judgement from the evidence, not a provable fact.

Why Messi:

• Awards: 8 Ballon d'Or wins to Ronaldo's 5, and 6 European Golden Shoes to 4.
• Scoring and creating: about 0.79 goals per game to 0.73, and roughly 424–463 assists to about 307.
• Head-to-head: 16 wins to 11 across their 36 meetings.
• World Cup: he won it in 2022 and was named best player of the tournament in 2014 and 2022. He also reached the 2026 final, which Argentina lost 1–0 to Spain after extra time.

Why Ronaldo:

• Totals: about 979 career goals to Messi's roughly 930.
• International records: most goals (146) and most caps (234) for a national team.
• Champions League: 5 titles and a record 140 goals.
• Range: top scorer in four different leagues and league titles in England, Spain and Italy.

The report is at artifacts/report.md. It keeps attributed facts in a sourced table, separate from my inferences, the uncertainties and the unanswered questions. A short README next to it states the question and its limits.

A few things to know before relying on the numbers:

• Some figures are unconfirmed. The head-to-head record and the 2026 calendar-year stats came from search summaries of Planet Football, 90min and GiveMeSport. I did not check them against match data.
• Wikipedia was read through an automated summariser. One summary gave clearly wrong club totals for Messi, so I left those out.
• Sources disagree slightly on Messi's totals: 929 or 931 goals, and 405 to 463 assists. None of this changes the verdict.
• Both players are still active, so the totals will keep moving.
• No independent review has been done. My own check only confirmed that the files exist and contain links, not that the research is true.

Both files are uncommitted, as required.