When I was looking chicks at hatchery, they said "90% accurate of sexing". But I bought my speckled sussex at feedstore and they said "they are all pullets, but no guarantee". They are only 3days old right now. (well I bought on Wednesday and they said one day old. But they got shipment on the morning. Are they really a day old??) Some are little bigger than others. Some are always pecking on someone. When I can tell, "yes, they are all pullets"??