On Prolific, you have the option to enter prescreening criteria to filter the participants you need.
Here are a few examples of the several hundred demographic criteria you can currently filter by:
- Country of Birth
- Current country of residence
- Within the United States: Current US state of residence and US state of birth
- First Language
- Employment status & domain
- Student status & field of study
- Political affiliation
- Religious affiliation
- Sexual orientation
- Marital status
- Socioeconomic status
- Participants' approval rate (how well did participants do in past studies?)
Check how many eligible participants we have for each criteria, by creating a study and going to the "Audience" tab (step 3). From there, you can select for the demographics you need by clicking "Custom prescreening". The system will then tell you the number of participants meeting your criteria.
Below, I'm selecting for US and UK Nationals. In the third image, you can see there are 39,783 eligible participants meeting this criteria, from an overall pool of 69,682 (first image).