Microsoft excel spreadsheet containing anonymised behavioural data from three experiments reported in the manuscript “Healthy ageing reduces the precision of episodic memory retrieval”. Sheet 1 contains data from Experiment 1, Sheet 2 data from Experiment 2, and Sheet 3 data from Experiment 3. Data were collected from healthy younger (aged 18 – 30) and older (aged 60 –82) individuals completing a computerized memory task. Two parameters of memory performance; the probability of successful memory retrieval (pT) and the precision of memory retrieval (Κ), were estimated for each participant and task condition with mixture modelling code available at https://www.paulbays.com/code/JV10/index.php. For Experiment 2, mean memory vividness is also reported for each participant. Variable names are defined in the “readme.txt” file. See the main manuscript for more details.