Fortinet (FTNT) stock is in focus after the company raised its 2026 revenue guidance to a range of US$8.02b to US$8.18b, indicating 19% year over year growth, alongside a fresh quarterly outlook.

At a share price of US$159.64, Fortinet has seen a 90 day share price return of 38.29% and a year to date share price return of 104.98%, while the 1 year total shareholder return stands at 114.60%, suggesting strong momentum around its raised guidance and recent product launches.

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Fortinet’s guidance lift and recent rally point to a business that many investors clearly rate highly. The next step is to see whether that enthusiasm is already fully reflected in the current valuation.

Most Popular Narrative: 27.1% Overvalued

According to the most followed Fortinet narrative, the fair value sits at $125.56 compared with the last close at $159.64, which implies a meaningful gap that valuation focused investors are watching closely.

Fortinet’s current valuation undoubtedly prices in a lot of future perfection, making it an expensive stock by traditional metrics. As of mid-July 2026, the stock trades at a Price-to-Earnings (P/E) ratio roughly 60x, which is a massive premium compared to the broader market and well above its recent 2024 and 2025 levels. Its Price-to-Sales (P/S) ratio tells a similar story, sitting at a lofty 16x to 18x, meaning investors are paying a steep multiple for every dollar of revenue the company brings in. While this premium reflects their explosive growth in AI infrastructure security, a P/E over 60 leaves almost zero room for error if macroeconomic conditions or spending on data centers slow down.

Curious what kind of revenue growth, margin profile, and future earnings multiple are baked into that fair value? The narrative for Fortinet leans heavily on AI infrastructure security, high profitability and a premium future P/E that treats the stock like a core compounder. Want to see exactly which financial assumptions are doing the heavy lifting in that calculation.

Result: Fair Value of $125.56 (OVERVALUED)

However, Fortinet’s rich P/E and P/S multiples, along with any slowdown in AI focused security spending, could quickly challenge the bullish fair value narrative.

Next Steps

With all this enthusiasm around Fortinet, it makes sense to check the numbers yourself and decide how much optimism you are comfortable with. To see what specific positives other investors are focused on, take a closer look at the 2 key rewards.

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This article by Simply Wall St is general in nature. We provide commentary based on historical data and analyst forecasts only using an unbiased methodology and our articles are not intended to be financial advice. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. We aim to bring you long-term focused analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Simply Wall St has no position in any stocks mentioned.