Okay, so we know it's best to choose a SPF 50 (although don't fret if your favourite formula is a SPF 30).
We then need to check that your SPF is broad-spectrum, meaning that it protects against both UVA and UVB rays - and don't worry, you don't need to study the INCI list - brands tend to advertise this on their packaging if it's broad-spectrum.
Next, consider your skin type. Dry skin will benefit from formulas with hyaluronic acid and humectants (like glycerin) and emollients (like squalane). If you're on the oily side or blemish-prone, there's plenty of oil-free formulas on the market. Sensitive skin? choose an SPF with a simple formula with fewer ingredients, and no fragrance.
Neutriherbs ultra light gel spf 50 is suitable for all skin types and made with no fragrance delivering high broad spectrum protection.