What does this number mean?
The sunspot number is an activity index based on the number of sunspot groups and individual spots visible on the Sun. It is not simply a count of spots. NOAA publishes the daily observed value shown here.
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Sunspot Number History & HF Propagation
Daily sunspot numbers provide a longer view of solar activity. Compare the last month, quarter or year, then combine the trend with current solar flux and geomagnetic conditions when planning HF operation.NOAA observed readings
Daily Sunspot Number
Latest reading: 96 on November 7, 2026.
Daily reading 30-day average
View daily values as a table
| Date | Sunspot number |
|---|---|
| Nov 7, 2026 | 96 |
| Nov 6, 2026 | 91 |
| Nov 5, 2026 | 89 |
| Nov 4, 2026 | 64 |
| Nov 3, 2026 | 41 |
| Nov 2, 2026 | 37 |
| Nov 1, 2026 | 30 |
| Oct 31, 2026 | 24 |
| Oct 30, 2026 | 36 |
| Oct 29, 2026 | 22 |
| Oct 28, 2026 | 12 |
| Oct 27, 2026 | 25 |
| Oct 26, 2026 | 25 |
| Oct 25, 2026 | 22 |
| Oct 24, 2026 | 25 |
| Oct 23, 2026 | 51 |
| Oct 22, 2026 | 49 |
| Oct 21, 2026 | 66 |
| Oct 20, 2026 | 66 |
| Oct 19, 2026 | 66 |
| Oct 18, 2026 | 82 |
| Oct 17, 2026 | 87 |
| Oct 16, 2026 | 81 |
| Oct 15, 2026 | 104 |
| Oct 14, 2026 | 124 |
| Oct 13, 2026 | 102 |
| Oct 12, 2026 | 93 |
| Oct 11, 2026 | 94 |
| Oct 10, 2026 | 99 |
| Oct 9, 2026 | 93 |
| Oct 8, 2026 | 69 |
| Oct 7, 2026 | 78 |
| Oct 6, 2026 | 77 |
| Oct 5, 2026 | 58 |
| Oct 4, 2026 | 55 |
| Oct 3, 2026 | 53 |
| Oct 2, 2026 | 37 |
| Oct 1, 2026 | 38 |
| Sep 30, 2026 | 29 |
| Sep 29, 2026 | 28 |
| Sep 28, 2026 | 46 |
| Sep 27, 2026 | 67 |
| Sep 26, 2026 | 88 |
| Sep 25, 2026 | 110 |
| Sep 24, 2026 | 124 |
| Sep 23, 2026 | 142 |
| Sep 22, 2026 | 126 |
| Sep 21, 2026 | 85 |
| Sep 20, 2026 | 54 |
| Sep 19, 2026 | 11 |
| Sep 18, 2026 | 0 |
| Sep 17, 2026 | 11 |
| Sep 16, 2026 | 23 |
| Sep 15, 2026 | 23 |
| Sep 14, 2026 | 51 |
| Sep 13, 2026 | 77 |
| Sep 12, 2026 | 87 |
| Sep 11, 2026 | 88 |
| Sep 10, 2026 | 90 |
| Sep 9, 2026 | 107 |
| Sep 8, 2026 | 102 |
| Sep 7, 2026 | 103 |
| Sep 6, 2026 | 83 |
| Sep 5, 2026 | 70 |
| Sep 4, 2026 | 72 |
| Sep 3, 2026 | 37 |
| Sep 2, 2026 | 73 |
| Sep 1, 2026 | 55 |
| Aug 31, 2026 | 81 |
| Aug 30, 2026 | 74 |
| Aug 29, 2026 | 73 |
| Aug 28, 2026 | 92 |
| Aug 27, 2026 | 76 |
| Aug 26, 2026 | 99 |
| Aug 25, 2026 | 83 |
| Aug 24, 2026 | 84 |
| Aug 23, 2026 | 73 |
| Aug 22, 2026 | 87 |
| Aug 21, 2026 | 59 |
| Aug 20, 2026 | 72 |
| Aug 19, 2026 | 78 |
| Aug 18, 2026 | 71 |
| Aug 17, 2026 | 76 |
| Aug 16, 2026 | 83 |
| Aug 15, 2026 | 111 |
| Aug 14, 2026 | 106 |
| Aug 13, 2026 | 101 |
| Aug 12, 2026 | 82 |
| Aug 11, 2026 | 62 |
| Aug 10, 2026 | 55 |
Daily readings: NOAA Space Weather Prediction Center. A missing date is left blank, not treated as zero. The optional average is calculated from 30 consecutive daily readings.
Why does it matter for HF?
Over weeks and months, higher sunspot activity is often associated with stronger ionization high in Earth's atmosphere. That can help higher HF bands, especially 15, 12, and 10 meters, support longer-distance contacts.
How should I use the graph?
Look for the direction of the trend, not a promise about a particular day or path. Today's openings also depend on solar flux, geomagnetic conditions, flares, daylight, season, and the stations at both ends of a contact.
Learn more from NOAA's solar cycle explanation and ARRL's HF propagation guide.