I'm surprised your low iron splash back changed the colour so much, is it starfire? There are green and clear glass, but the thickness varies white the most. Trying to match your whites perfectly will always result in a slight variation, because the products different it's almost impossible. Very subtle tonal differences can be disguised if your splash back is enclosed or surrounded by joinery as the shadowing created allows for discrepancy. Otherwise, make colour difference intentional and find something that can coordinate and not copy the colour. Maybe mirror and remove colour from the equation

Thanks. House completed a while back. Builder did all trim and doors in vivid white. Ceilings in ceiling white. Left it to them.

Amber, there are so many whites and much to take into consideration when deciding which colours suit you, your style and the rest of your home. For example, what is your kitchen wall colour and the colour of any adjacent walls? What material will be used for your cabinets? What floor coverings are in the kitchen and surrounding areas, and what are their colours? Do you want a laminate, engineered stone, marble or granite benchtop? Warm white or cool white? I believe once you have narrowed the field a bit, suggestions will follow.

Paint swatches are your friend here, either sample pots or the A4 size that Dulux introduced. Paint looks different in different lighting and surroundings. Our, barest touch of blue, interior paint, has one wall that throws a bit grey in certain light - the one thing I was trying to avoid - but is perfect everywhere else 🤷🏻‍♀️ . The initial favourite, while the paint chip was very similar seemed over saturated. It’s definitely worth a visit to the paint specialty stores, many have colour consultants, if you’re still undecided. We also found them less expensive, too.