Topic Radar tracks the topics heating up across the web — Hacker News, Reddit, X, YouTube, Google Trends and the major news outlets — and ranks them by a heat score built from verifiable evidence. It is a topic radar for creators: find what people are actually talking about, understand the real problem behind the buzz, and take an angle to make content from it.
The heat score
Each topic gets three sub-scores. Rank score (40%): where it sits on the charts — #1 is 100, #2–3 is 95, #4–5 is 90, #6–10 is 85, #11–20 is 75, new without a rank is 60. Discussion score (40%): how much people are talking about it — 10M+ mentions is 100, 5–10M is 90, 1–5M is 80, 500K–1M is 70, 100–500K is 60. Cross-platform score (20%): how many platforms it is spreading across — 4+ is 90, 3 is 70, 2 is 50, 1 is 30. Composite = rank × 0.4 + discussion × 0.4 + cross-platform × 0.2, to one decimal place.A topic that has clearly cooled — gone from the top 20 or visibly fading — takes a 20-point decay on the composite score only. The three sub-scores stay as measured, so the decay is visible rather than hidden inside a recomputation.
Source tiers
Every topic carries a source tier. T1 is an official announcement, filing or dataset itself. T1.5 is an official account, company statement or on-the-record response. T2 is media, a person or a chart. A topic is marked for review when it rests on a single weak source or an unverified claim. Tiers are recorded, they do not change the score.
What rising and cooling mean
Rising means the topic is still gaining heat: new ranks, new discussion, new platforms. Cooling means the peak has passed and attention is fading — the topic is still listed because it was hot, not because it is still worth chasing. Timeliness is a judgement about whether the topic is still worth making content about, not a prediction.
What we do not do
We do not invent topics, scores or evidence. Every number on this site comes from the tracked charts and the linked sources. Where a claim could not be verified, the topic says so. A single viral post with no verifiable trail is a local signal, not a hot topic.