Have you looked on your local council's website? There should be links to the schools' own websites.
In some local education authorities, schools have fixed catchment areas and you're either in or out. In others (like mine) places are awarded on distance to school, so after looked-after children, those with statements naming the school and siblings have been admitted, it's the 10/20/50/whatever living nearest who get in. The school or the LEA should be able to tell you the farthest distance at which a place was awarded for any school.
Thank you no I haven't looked on the council website but did google it and looked on the schools websites. Looked at Ofsted website too so I think my area may be like yours Tommy and have changing areas. I'll try now though.
For our county, there is a page where they tell you which roads would suggest you should go to which schools. But it can't ever be exact as there will be different amounts of children applying in different years.
Worth calling the council as some schools don't actually have catchment areas. From what I understand, it isn't a hard and fast rule, where there is a specific cut off point, but rather the areas are guidelines only. So, if there was a child who was next door to the school, but you had a child already at the school, it would be down to their policy as far as who takes priority.