Fortinet (WBO:FTNT) Cyclically Adjusted PB Ratio: (As of Sep. 15, 2026)

Author: Vera Yuan Vera Yuan
Vera Yuan
Vera Yuan
Director of Data and Quant Analytics at GuruFocus
Focused on building reliable datasets, financial models, and research tools for value-minded investors. Committed to turning complex data into practical guidance for value-investing and long-term wealth.
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Charlie Tian
Charlie Tian
Founder & CEO of GuruFocus
Dr. Charlie Tian is the founder and CEO of GuruFocus.com, a leading global investment research platform established in 2004. With a Ph.D. in physics, Dr. Tian transitioned from science to finance, applying a data-driven, disciplined approach to value investing.

WBO:FTNT Fortinet Inc WBO:FTNT
87 GF Score
Price €146.16
GF Value €91.74
! 4 Warning Signs
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What is Fortinet Cyclically Adjusted PB Ratio?

Note: If the price history is too short, we do not calculate current Cyclically Adjusted PB Ratio for this stock. All the historical data is shown as the company's primary share's data instead.

Shiller PE for Stocks: The True Measure of Stock Valuation


Fortinet  (WBO:FTNT) Cyclically Adjusted PB Ratio Explanation

Compared with the regular PB Ratio, which works poorly for cyclical businesses, the Cyclically Adjusted PB Ratio smoothed out the fluctuations of book value during business cycles. Therefore it is more accurate in reflecting the valuation of the company.

If a company has consistent business performance, the Cyclically Adjusted PB Ratio should give similar results to regular PB Ratio.


Fortinet Cyclically Adjusted PB Ratio Related Terms


Fortinet Cyclically Adjusted PB Ratio Historical Data

* Premium members only.

The historical data trend for Fortinet's Cyclically Adjusted PB Ratio can be seen below:

* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD.
* For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.

Fortinet Cyclically Adjusted PB Ratio Chart

Fortinet Annual Data
Trend Dec16 Dec17 Dec18 Dec19 Dec20 Dec21 Dec22 Dec23 Dec24 Dec25
Cyclically Adjusted PB Ratio
Get a 7-Day Free Trial Premium Member Only Premium Member Only 69.31 49.11 62.70 100.50 76.12

Fortinet Quarterly Data
Sep21 Dec21 Mar22 Jun22 Sep22 Dec22 Mar23 Jun23 Sep23 Dec23 Mar24 Jun24 Sep24 Dec24 Mar25 Jun25 Sep25 Dec25 Mar26 Jun26
Cyclically Adjusted PB Ratio Get a 7-Day Free Trial Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only 102.28 81.31 76.12 76.61 139.73

WBO:FTNT vs : Cyclically Adjusted PB Ratio Comparison

For the Software - Infrastructure subindustry, Fortinet's Cyclically Adjusted PB Ratio, along with its competitors' market caps and Cyclically Adjusted PB Ratio data, can be viewed below:

* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.


Fortinet Cyclically Adjusted PB Ratio vs Software Industry

For the Software industry and Technology sector, Fortinet's Cyclically Adjusted PB Ratio distribution charts can be found below:

* The bar in red indicates where Fortinet's Cyclically Adjusted PB Ratio falls into.


WBO:FTNT
87GF Score
Fortinet Inc WBO:FTNT
Cyclically Adjusted PB Ratio is just one metric. See GF Score™, valuation, warning signs, and more.
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Fortinet Cyclically Adjusted PB Ratio Calculation

Like the Shiller PE Ratio, the Cyclically Adjusted PB Ratio takes the Book Value per Share from the past 10 years, adjusts it for inflation, and then calculates the average. This average is then used for the P/B calculation. Because it considers this 10-year average, it's often referred to as the CAPB Ratio.

The Shiller PE Ratio was first used by professor Robert Shiller to measure the valuation of the overall market. The similar calculation is applied by GuruFocus to calculate the Cyclically Adjusted PB Ratio.

Fortinet's Cyclically Adjusted Book per Share for the quarter that ended in Jun. 2026 is calculated as:

For example, Fortinet's adjusted Book Value per Share data for the three months ended in Jun. 2026 was:

Adj_Book=Book Value per Share/CPI of Jun. 2026 (Change)*Current CPI (Jun. 2026)
=1.838/333.9520*333.9520
=1.838

Current CPI (Jun. 2026) = 333.9520.

Fortinet Quarterly Data

Book Value per Share CPI Adj_Book
201609 0.845 241.428 1.169
201612 0.918 241.432 1.270
201703 0.957 243.801 1.311
201706 0.934 244.955 1.273
201709 0.867 246.819 1.173
201712 0.593 246.524 0.803
201803 0.670 249.554 0.897
201806 0.790 251.989 1.047
201809 0.897 252.439 1.187
201812 1.046 251.233 1.390
201903 1.097 254.202 1.441
201906 1.162 256.143 1.515
201909 1.273 256.759 1.656
201912 1.407 256.974 1.828
202003 0.597 258.115 0.772
202006 0.597 257.797 0.773
202009 0.746 260.280 0.957
202012 0.866 260.474 1.110
202103 1.009 264.877 1.272
202106 1.068 271.696 1.313
202109 1.163 274.310 1.416
202112 0.854 278.802 1.023
202203 0.247 287.504 0.287
202206 -0.471 296.311 -0.531
202209 -0.822 296.808 -0.925
202212 -0.340 296.797 -0.383
202303 0.014 301.836 0.015
202306 0.377 305.109 0.413
202309 0.089 307.789 0.097
202312 -0.558 306.746 -0.607
202403 -0.166 312.332 -0.177
202406 0.350 314.175 0.372
202409 1.069 315.301 1.132
202412 1.860 315.605 1.968
202503 2.360 319.799 2.464
202506 2.334 322.561 2.416
202509 0.843 324.800 0.867
202512 1.422 324.054 1.465
202603 1.166 330.213 1.179
202606 1.838 333.952 1.838

Add all the adjusted book value per share together and divide the count will get our Cyclically Adjusted Book per Share.

Please note that we use the CPI data of the country/region where the company is headquartered. If the CPI data for that country/region is not available, then we will use the CPI data of the United States as default.

Is Fortinet (WBO:FTNT) Overvalued in 2026?

Based on GuruFocus' analysis, Fortinet stock appears to be overvalued. The current stock price of €146.16 is trading 59.3% above its estimated GF Value™ of €91.74.

Key valuation signals for WBO:FTNT:

  • Cyclically Adjusted PB Ratio:
  • GF Value™: €91.74 vs. price of €146.16 (59.3% above fair value)
  • GF Score™: 87/100 with 4 warning signs

No single metric tells the full story. See the WBO:FTNT stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.


Fortinet Business Description

Comparable Companies
Address 909 Kifer Road, Sunnyvale, CA, USA, 94086
Fortinet is a platform-based cybersecurity vendor with product offerings covering network security, cloud security, zero-trust access, and security operations. The firm derives a majority of its revenue through sales of its subscriptions and support-based business. The California-based firm has more than 800,000 customers across the world.
87GF Score

Get the complete analysis for WBO:FTNT

Cyclically Adjusted PB Ratio is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.

€146.16
Price
€91.74
GF Value