Pollen & Allergy Tracker
Should I go outside today?
Pollen count today for 800+ US, UK & Canada cities — with a clear YES, CAUTION, or NO answer.
Pollen Across the US, UK & Canada
Worst Pollen Cities Right Now
Cities with the highest pollen levels right now.
Compare with AAFA's 2026 Annual Allergy Capitals →
I built PollenTracker because my 6-year-old son is severely allergic to pollen. Every morning I needed one simple answer: should we go outside today?
📊 Quick Reference
Pollen Count Levels
Thresholds and how we read today's data.
What pollen count is considered high?
Different pollen types have different thresholds. The National Allergy Bureau categorizes counts (grains per cubic meter of air) like this:
| Pollen type | Low | Medium | High | Very High |
|---|---|---|---|---|
| Tree | 1–14 | 15–89 | 90–1,499 | 1,500+ |
| Grass | 1–4 | 5–19 | 20–199 | 200+ |
| Weed | 1–9 | 10–49 | 50–499 | 500+ |
| Mold | 1–6.4k | 6.5k–13k | 13k–50k | 50k+ |
For most allergy-sensitive readers, symptoms start at the medium threshold. By high, expect persistent congestion and watery eyes; very high counts often intensify respiratory symptoms in sensitive groups.
How we decide YES, CAUTION, or NO
Most pollen apps show a number and walk away. PollenTracker translates the data into a decision:
- YES: Low pollen + good air quality (AQI under 50).
- CAUTION: Medium pollen, or AQI 51–100, or both.
- NO: High or very high pollen, or AQI 101+.
We weight pollen severity around 60%, air quality 30%, and weather amplifiers like wind speed 10%.
Live data from Google Pollen Forecast · Google Air Quality · OpenWeather
Pollen & Allergy FAQ
What is pollen count and why does it matter?
Pollen count is a snapshot of how many pollen grains are floating in the air per cubic meter, measured at certified sampling stations or projected through forecasting models. Higher counts trigger allergy symptoms like sneezing, congestion, and watery eyes. When you check pollen count today, you're seeing the prediction for the next 24 hours — not a multi-day forecast. PollenTracker pulls live data from Google's Pollen Forecast API and covers 800+ cities across the US and UK.
When is pollen season in the US?
Tree pollen peaks from March to May (oak, birch, maple, and cedar are the heavy hitters). Grass pollen takes over from May to July (Bermuda, ryegrass, timothy). Ragweed dominates August through October — a single plant can release up to a billion grains per fall season. Southern states start earlier; Northern states have a compressed but intense season.
When is hayfever season in the UK?
UK hayfever season runs from late March through September. Tree pollen (mainly birch and alder) peaks April-May; grass pollen — the main trigger for most UK hayfever sufferers — peaks May-July; weed pollen extends into September. Scotland's season typically runs 2-3 weeks later than England. Hayfever affects roughly 1 in 4 adults in the UK.
What pollen types do you track?
Three main pollen types drive most allergy seasons. Tree pollen (March-May): oak, birch, maple, cedar in the US; birch and alder in the UK — heaviest in dry, windy mornings. Grass pollen (May-July): Bermuda, ryegrass, timothy. Weed pollen (August-October): ragweed dominates the US fall, with nettle and dock more common in the UK. We track the dominant type per city per day and weight it into the overall YES/CAUTION/NO score.
How does PollenTracker decide if it's safe to go outside?
We translate the data into a clear three-way decision. YES means low pollen + good air quality (AQI under 50). CAUTION means medium pollen, or AQI 51-100, or both. NO means high or very high pollen, or AQI 101+. We weight pollen severity around 60%, air quality 30%, and weather amplifiers like wind speed 10%.
What's the difference between pollen count and air quality index?
Pollen count measures allergen particles from plants, primarily affecting allergy sufferers. The Air Quality Index (AQI) measures pollutants like PM2.5 and ozone that affect everyone's respiratory health. PollenTracker tracks both to give you the full picture — both factor into the YES/CAUTION/NO decision.
When should I check pollen count?
Quick rules of thumb: morning (6-10 AM) is when pollen peaks — check before opening windows or sending kids outside. Before exercise, outdoor running or biking exposes you to up to 10× more pollen than indoor activity. After rain, counts drop temporarily — a great window if you've been cooped up. Late afternoon (4-6 PM) is the second-best window. Bookmark PollenTracker or scroll up to subscribe to our daily email so this 5-second check happens automatically every morning.
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