Purpose: Seeking online bilingual scientific information is a key aspect of bilingual scientific Web literacy -- abilities to engage critically with science on the Web using two languages. This study aims to determine whether factors such as age, education major, gender and type of school attended at secondary level (monolingual, bilingual, trilingual) influence undergraduates' ability to search online Spanish-English bilingual scientific information. Design/methodology/approach: The participants in this study were 60 students (43 females and 17 males, 18-25 years old) enrolled in a university bilingual science course at a high-ranked Colombian university. They were asked to complete two tasks in which they had to seek online scientific information in Spanish and in English and post their responses on the Web application, Padlet® (padlet.com). Findings: Results indicate that students' gender and age influence their academic performance in both tasks and level of originality in using information obtained via the Web, respectively. Moreover, the "scientific journal" was the top source of online information from which participants sought most information to complete both tasks. Originality/value: People are becoming increasingly accustomed to seeking and sharing online scientific information to support points of view and make decisions. However, it is not known which factors influence students' ability to seek online first language-English bilingual scientific information in countries where English is the second or foreign language.