Sirups

Generally measure by weight. If heating water to mix, some water will evaporate. Consider adding it back in afterwards.

Add a tablespoon of vodka and it will last longer

Simple

1x Sugar
1x Water

Rich Simple

2x Sugar
1x Water

Same sweetening power as 1.5x of regular Simple Sirup¹

Honey Sirup

64g Water
100g Honey

Ratio from Liquid Intelligence. You should be able to use this ratio in place of simple syrup in any recipe.

Other ratios such as 1:1, 2:1 and 3:1 are being mentioned in a lot of places. Difford’s seems to prefer a 3:1 ratio.

Berries

100g Berries (Strawberry, Raspberry, ..)
2dl Sugar
1dl Water

Process: Muddle berries with sugar. Heat water to just below boiling point. Add sugar/berry-mix and stir until the sugar is dissolved.

Didn’t write down the recipe when I made it last time, so haven’t actually tried these exact ratios. I guess the sugar should be adjusted depending on the sweetness of the berries.

Coconut Syrup / Cream of Coconut

400 ml Coconut Milk (1 can)
375 g Sugar
Pinch of salt

Process: Stir over heat until sugar is dissolved (color changes from white to partially transparent)

See Steve

Mint Syrup

Pineapple Syrup

? https://drinkinghobby.com/pineapple-syrup-recipe/

Liquid Intelligence by Dave Arnold p. 51