Is sihr real, and what does Islam say about it?

The Quran treats sihr as real, not as superstition. Surah Al-Baqarah describes what was revealed at Babylon and states plainly that people learned from it what could divide a husband from his wife, while making clear that nothing harms anyone except by the permission of Allah.

Surah Al-Falaq instructs believers to seek refuge from those who blow on knots, a direct reference to a technique of sihr. The Prophet, peace be upon him, was himself affected by sihr, and Allah revealed the two protective surahs in response.

Two things follow from this. First, dismissing sihr entirely contradicts clear texts. Second, and just as important, sihr operates only within what Allah permits. It is not an independent power, and it cannot override divine decree.

That second point is what keeps fear in proportion.