This study analyzed the fatty acid (FA) compositions of thirty-nine vegetable oils and fats, including nangai nut, pili nut, shea butter, tamanu oil, baobab, sea buckthorn berry, Brazil nut, grape seed, black seed, evening primrose, passion fruit, milk thistle, sunflower, pumpkin seed, sesame, soybean, flax seed, kukui, red raspberry seed, walnut, chia seed, hemp seed, rosehip, almond, avocado, carrot seed, moringa, apricot kernel, camellia seed, macadamia, olive, marula, argan, castor, jojoba, pomegranate seed, medium-chain triglyceride (MCT) coconut, roasted coconut, canola, and mustard oil, using gas chromatography–mass spectrometry (GC-MS). The results showed that these oils and fats have different FA compositions, with saturated and unsaturated FAs being the main categories. Roasted coconut oil had the highest saturated FA content, while passion fruit oil had the highest linoleic acid content, and chia seed oil had the highest linolenic acid content. Camellia seed oil contained exclusively oleic acid, and mustard oil had a significant amount of erucic acid. Jojoba oil was primarily composed of (Z)-11-eicosenoic acid and (Z)-docos-13-en-1-ol. Castor oil was mainly ricinoleic acid. The study also highlighted the importance of essential FAs in maintaining health and the potential risks of (E)-FAs. The findings provide a chemical fingerprint of various vegetable oils and fats, which can be used for authentication and to guide their use in biofuel production, cosmetics, and pharmaceutical industries. The study emphasizes the need for consumers to be aware of the FA compositions of the oils they consume and to make informed choices based on their health and dietary needs.This study analyzed the fatty acid (FA) compositions of thirty-nine vegetable oils and fats, including nangai nut, pili nut, shea butter, tamanu oil, baobab, sea buckthorn berry, Brazil nut, grape seed, black seed, evening primrose, passion fruit, milk thistle, sunflower, pumpkin seed, sesame, soybean, flax seed, kukui, red raspberry seed, walnut, chia seed, hemp seed, rosehip, almond, avocado, carrot seed, moringa, apricot kernel, camellia seed, macadamia, olive, marula, argan, castor, jojoba, pomegranate seed, medium-chain triglyceride (MCT) coconut, roasted coconut, canola, and mustard oil, using gas chromatography–mass spectrometry (GC-MS). The results showed that these oils and fats have different FA compositions, with saturated and unsaturated FAs being the main categories. Roasted coconut oil had the highest saturated FA content, while passion fruit oil had the highest linoleic acid content, and chia seed oil had the highest linolenic acid content. Camellia seed oil contained exclusively oleic acid, and mustard oil had a significant amount of erucic acid. Jojoba oil was primarily composed of (Z)-11-eicosenoic acid and (Z)-docos-13-en-1-ol. Castor oil was mainly ricinoleic acid. The study also highlighted the importance of essential FAs in maintaining health and the potential risks of (E)-FAs. The findings provide a chemical fingerprint of various vegetable oils and fats, which can be used for authentication and to guide their use in biofuel production, cosmetics, and pharmaceutical industries. The study emphasizes the need for consumers to be aware of the FA compositions of the oils they consume and to make informed choices based on their health and dietary needs.