Online panel company	Total panel size*
YouGov	300,000
Ipsos-i-Say	500,000
Mfour (mobile only)	602,000
Luth Research	1,000,000
Instantly (formally uSamp)	1,000,000
LightSpeed	1,700,000
Toluna	2,300,000
NPD – VIP Voice	2,500,000
Research Now	3,000,000
SurveySpot, OpinionWorld	3,000,000
Harris	6,000,000
Prodege MR	11,000,000
Total	32,902,000