Ideal protein as a concept has been around for a number of years. The data necessary to formulate an ideal protein based diet include amino acid digestibility of major feedstuffs, a working estimate of an ideal protein for turkeys, a workable low protein diet for determining amino acid requirements via titration and requirement data for the limiting amino acids. Previous research in our lab has collected data on all of these areas leading to an estimate of the ideal protein for turkeys (Missouri Ideal Turkey Protein). The objective of this work is to test the collected data in turkeys to market age and determine if the estimated ideal protein is accurate and if cost savings would result. An experiment was conducted with 800 Nicholas toms in a floor pen setting. Birds were placed in a curtain-sided building with circulating fans on used litter. Toms were moved from brooder to finisher at 8 weeks of age and processed at the conclusion of the trial for parts yield. Eight replicate pens of 25 toms per pen were used for a total of 32 pens. Birds were weighed at 3 week intervals. All diets were computer formulated using an industry provided premix and readily available feedstuffs that are commonly used throughout the industry. The control diets were industry average diets based on Agristats information. These diets were formulated on a total amino acid basis as per their data. The other diets were formulated on a digestible amino acid basis using constraints based on our research. All digestibility values were obtained using cecectomized hens with gavage feeding and total fecal collection. Treatments consisted of the following: 1) Control, 2) Exact requirements on a digestible Amino Acid (AA) basis with no safety factor (Ideal), 3) Ideal + 5% AA safety factor (recommended diet), 4) Ideal + 10%. Performance of the ideal protein diet was slightly reduced at 3 wks of age. The addition of 5 or 10% amino acids brought growth back to even with the industry diet at that time. No differences in performance were noted through 15 weeks. At 18 weeks the ideal protein diet was significantly lighter in weight (4.8%) than the industry diet while the diets with 5 or 10% AA additions did not differ from the control. Small differences in feed efficiency occurred through different phases of the trial, but there were no differences at the conclusion of the trial. No differences in mortality or parts yield were noted. Significant cost reductions were found in diets formulated based on the Missouri Ideal Turkey Protein.