Brandwave

How popular isMicrosoft Defender?

In September 2026, people searched for Microsoft Defender by name about 181,000 times worldwide, a 26.1% decrease from the previous year. These searches made up 7.5% of all global antivirus software searches, placing Microsoft Defender fourth out of seven brands. When we asked both ChatGPT and Google AI Overviews about antivirus software, Microsoft Defender appeared in all answers and was the third most recommended of the seven.

Search and AI answers in September 2026

Microsoft Defender is the fourth most searched of 7 competitors and the third most recommended in AI answers.

  1. NortonShare of searches 39.2%Mentioned in 4 of 4 AI answersPlace in AI recommendations 2nd
  2. McAfeeShare of searches 25.4%Mentioned in 1 of 4 AI answersPlace in AI recommendations 5th
  3. KasperskyShare of searches 22.9%Mentioned in 0 of 4 AI answersPlace in AI recommendations –
  4. Microsoft DefenderShare of searches 7.5%Mentioned in 4 of 4 AI answersPlace in AI recommendations 3rd
  5. BitdefenderShare of searches 3.8%Mentioned in 4 of 4 AI answersPlace in AI recommendations 1st

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Top antivirus software in ChatGPT and Google AI Overviews

In three ChatGPT questions and one Google AI Overview, Microsoft Defender appeared in all four answers. Microsoft Defender is the third most recommended of the seven.

Most recommended by AI

Brands get a higher ranking if they are mentioned earlier in the answers.

  1. Bitdefender1st
  2. Norton2nd
  3. Microsoft Defender3rd
  4. Malwarebytes4th
  5. McAfee5th
  6. ESET6th
  7. Kaspersky–

Mentioned by AI

Each dot is one answer, filled in when that answer mentions the brand.

  • Norton4 of 4Named in 3 of 3 ChatGPT answersNamed in 1 of 1 Google answers
  • Microsoft Defender4 of 4Named in 3 of 3 ChatGPT answersNamed in 1 of 1 Google answers
  • Bitdefender4 of 4Named in 3 of 3 ChatGPT answersNamed in 1 of 1 Google answers
  • ESET2 of 4Named in 2 of 3 ChatGPT answersNamed in 0 of 1 Google answers
  • Malwarebytes2 of 4Named in 1 of 3 ChatGPT answersNamed in 1 of 1 Google answers
  • McAfee1 of 4Named in 0 of 3 ChatGPT answersNamed in 1 of 1 Google answers
  • Kaspersky0 of 4Named in 0 of 3 ChatGPT answersNamed in 0 of 1 Google answers

See every answer about antivirus software

4 answers

Not named in any answer:

Brands are shown in the order each answer named them. The survey took place in the United States on October 20, 2026.

Which antivirus software compete with Microsoft Defender?

Microsoft Defender against antivirus software worldwide, by month

Share of searches by month for Norton, McAfee, Kaspersky, Microsoft Defender, Bitdefender. The figures are in the table below the chart.

View monthly share of searches table
MonthNortonMcAfeeKasperskyMicrosoft DefenderBitdefenderESETMalwarebytes
Oct 202537.2%27%23.2%8.4%3.1%0.93%0.12%
Nov 202535.5%28.3%24.9%7.4%2.7%1%0.11%
Dec 202535.3%28.4%25%7.5%2.8%1%0.11%
Jan 202635%31.4%22.7%7.4%2.5%0.91%0.1%
Feb 202636.3%30.4%21.9%8%2.4%0.88%0.12%
Mar 202635.9%30.8%21.6%7.9%2.9%0.87%0.11%
Apr 202634.3%28.3%24.3%8.8%3.3%0.98%0.13%
May 202633.8%28.9%24.9%9.1%2.2%1%0.13%
Jun 202636.5%29.8%22%8%2.4%1.1%0.12%
Jul 202635.6%28.6%21.5%7.8%5.2%1.1%0.11%
Aug 202636.1%27.3%24.6%8.1%2.7%1.2%0.11%
Sep 202639.2%25.4%22.9%7.5%3.8%1.1%0.1%

  1. 1.Norton

    39.2%

    Held 1st. 943K estimated branded searches, +16.9% vs prior month. Share +3.2 points.

  2. 2.McAfee

    25.4%

    Held 2nd. 611K estimated branded searches, 0% vs prior month. Share -1.9 points.

  3. 3.Kaspersky

    22.9%

    Held 3rd. 550K estimated branded searches, 0% vs prior month. Share -1.7 points.

  4. 4.Microsoft Defender

    7.5%

    Held 4th. 181K estimated branded searches, 0% vs prior month. Share -0.6 points.

  5. 5.Bitdefender

    3.8%

    Held 5th. 90.5K estimated branded searches, +49.6% vs prior month. Share +1.1 points.

  6. 6.ESET

    1.1%

    Held 6th. 27.1K estimated branded searches, 0% vs prior month. Share -0.1 points.

  7. 7.Malwarebytes

    0.1%

    Held 7th. 2.4K estimated branded searches, 0% vs prior month. Share 0 points.

Compare popularity between Microsoft Defender and its closest rivals

Every comparison with Microsoft Defender

12 comparisons

How has branded search demand for Microsoft Defender changed worldwide over the last 12 months?

3 findings
  • Across the 12 months ending September 2026, estimated monthly branded searches for Microsoft Defender worldwide fell from 245K to 181K.
  • Across the 12 months ending September 2026, Microsoft Defender’s share of searches among antivirus software worldwide decreased from 8.4% to 7.5%.
  • Across the 12 months ending September 2026, Microsoft Defender’s share of searches among antivirus software worldwide peaked at 9.1% in May 2026 and was lowest at 7.4% in January 2026.

How did search popularity change for antivirus software worldwide in September 2026?

6 changes

  1. In September 2026, Norton gained share of searches among antivirus software worldwide, from 36.1% to 39.2%.

  2. In September 2026, Bitdefender gained share of searches among antivirus software worldwide, from 2.7% to 3.8%.

  3. In September 2026, McAfee lost share of searches among antivirus software worldwide, from 27.3% to 25.4%.

  4. In September 2026, Kaspersky lost share of searches among antivirus software worldwide, from 24.6% to 22.9%.

  5. In September 2026, Microsoft Defender lost share of searches among antivirus software worldwide, from 8.1% to 7.5%.

  6. Estimated monthly branded searches for Malwarebytes worldwide fell 33.3% over 12 measured months, from 3.6K to 2.4K in September 2026.

How are Microsoft Defender’s branded searches counted?

2 search terms

Brandwave collects information about searches that people make online using Microsoft Defender’s name. When viewed over time, estimated search volumes for these branded terms can be used to understand whether interest in the brand is growing, holding steady, or fading.

  • microsoft defender
  • windows defender

Do you work for Microsoft Defender? To request corrections or removal please contact us via our support page and we will be happy to assist.

How the Brand Demand Index is measured

Where does Microsoft Defender compete?

Microsoft Defender is ranked in three competitor sets. Each share is worked out among that set's brands, so it differs from set to set.
Competitor setRankShare of searchesRanking
Endpoint security software6th of 86.5%Show ranking
Antivirus software4th of 77.5%Shown above
Endpoint detection platforms2nd of 733.6%Show ranking
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Is Microsoft Defender your brand?

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