Short answer
It depends on why. Trimming a few long or stray hairs so your brows look normal is allowed in the Hanafi school, for men and women. Cutting, shaving or trimming the brows into a thinner or new shape for beauty is the forbidden namas, whatever tool you use.
Trimming eyebrow hairs that are unusually long or bushy, to bring them back to a normal look, is permissible. Thinning or reshaping the brows for beauty is haram for women, and for men it is also imitation of women.
The four schools agree on this.
Explanation
The hadith of Ibn Mas'ud curses those who pluck their eyebrows to beautify themselves, changing the creation of Allah. The word used is about plucking, but the Hanafi scholars look at the reason the hadith gives: changing a normal feature for beauty. So the method does not matter. Plucking, threading, waxing, shaving and cutting to shape all take the same ruling.
What the Hanafi texts allow is tidying. Al-Fatawa al-Hindiyya says there is no harm in taking from the eyebrows as long as one does not end up looking like effeminate men. Muftis explain this as trimming hairs that hang into the eyes, the long wiry hairs that often appear with age, or brows so thick that they look unusual, and bringing them back to an ordinary look.
- Allowed: snipping a few long or curling hairs with small scissors, brushing the brows into place, or using a clear brow gel.
- Not allowed: cutting them shorter to sharpen the shape, trimming them into a thin line, shaving them off to draw new ones, or cutting slits.
- A simple test: if an ordinary person would notice that your brows have been shaped, you have gone too far.
If you have shaped your brows in the past, repent and let them grow back; there is nothing to make up, and your wudu and prayers were valid. Related answers: removing a unibrow, eyebrow slits and bleaching or tinting eyebrows.
The evidence
Quran, Surah An-Nisaa 4:119
وَلَأُضِلَّنَّهُمْ وَلَأُمَنِّيَنَّهُمْ وَلَءَامُرَنَّهُمْ فَلَيُبَتِّكُنَّ ءَاذَانَ ٱلْأَنْعَٰمِ وَلَءَامُرَنَّهُمْ فَلَيُغَيِّرُنَّ خَلْقَ ٱللَّهِ ۚ وَمَن يَتَّخِذِ ٱلشَّيْطَٰنَ وَلِيًّۭا مِّن دُونِ ٱللَّهِ فَقَدْ خَسِرَ خُسْرَانًۭا مُّبِينًۭا ﴿١١٩﴾
And I will mislead them, and I will arouse in them [sinful] desires, and I will command them so they will slit the ears of cattle, and I will command them so they will change the creation of Allah." And whoever takes Satan as an ally instead of Allah has certainly sustained a clear loss.
Satan's promise to make people change Allah's creation, the reason the scholars give for the ruling on namas.
Sahih al-Bukhari 4886
Sahih... والمتنمصات والمتفلجات للحسن المغيرات خلق الله ...
"Allah has cursed the women who tattoo and have tattoos done, who pluck their eyebrows, and who file gaps in their teeth for beauty, changing the creation of Allah."
Ibn Mas'ud's report of the curse on namas (plucking or reshaping the eyebrows), which he said the Prophet ﷺ had cursed.
Where the ruling is recorded
- al-Fatawa al-Hindiyya, Kitab al-Karahiyya, chapter on circumcision, hair and nails. Taking from the eyebrows is allowed as long as it does not resemble the effeminate.
- Radd al-Muhtar (Ibn Abidin), Kitab al-Hazr wa al-Ibaha, section on looking and touching. Ibn Abidin's explanation of namas and the reason behind it.
Checked by our team. For a more accurate answer to your own situation, consult a scholar. Quran translation by Sahih International. Hadith Arabic from the standard editions of the six books and the Muwatta, with gradings as recorded there; the English is our own rendering. Spotted a mistake? Tell us.