Gender API Example https://gender-api.com/en/

gender.R

#' Gets gender by name or email address, optionally by country or IP address.

library("httr")
library("XML")

#' @import httr
#' @import rjson
#' @param name A character string containing a first name, or a character vector containing first names. One must specify name or email.
#' @param email A character string containing an email address with a first name. One must specify name or email.
#' @param country An optional character string containing a two-letter country name, as listed here: https://gender-api.com/en/api-docs
#' @param ip An optional character string containing an IP address, used in place of country.
#' @return A dataframe containing the estimated gender, number of samples that estimate is based upon, an accuracy metric (ranging from 0 to 100), and the length of time for the server to process the request.
#' @export
#' @examples \dontrun{
#' gender('Andrea', country='US')
#' gender('Andrea', country='IT')
#' gender(c('george','thomas','ben'))
#' }

gender <- function(name=NULL, email=NULL, country=NULL, ip=NULL){
    args <- list()
    if(!is.null(name)){
        if(length(name)>1)
            args$name <- paste(head(unique(name),100), collapse=';')
        else
            args$name <- name
        if(length(name)>100)
            warning("Only first 100 names will be used!")
    }
    if(!is.null(email))
        args$email <- email
    if(!is.null(country))
        args$country <- country
    if(!is.null(ip))
        args$ip <- ip
    result <- GET('https://gender-api.com/get', query=args)
    out <- content(result)
    if(grepl('errno', content(result,as='text')))
        stop(out$errmsg)
    if((!is.null(name) & length(name)==1) || !is.null(email))
        out <- as.data.frame(out)
    else
        out <- do.call(rbind.data.frame,out$result)
    rownames(out) <- 1:nrow(out)
    return(out)
}

#' @import httr
#' @import XML
#' @return A dataframe containing the country name and two-letter shortcut for every country available via the API.
#' @export
#' @examples \dontrun{
#' genderCountryCodes()
#' }

genderCountryCodes <- function(){
    html <- htmlParse(GET("https://gender-api.com/en/api-docs"))
    out <- cbind.data.frame(name = xpathSApply(html, "//div[@class='country clearfix']//div[@class='name']", xmlValue),
                            shortcut = xpathSApply(html, "//div[@class='country clearfix']//div[@class='shortcut']", xmlValue))
    return(out)
}

I emailed the developer. Seems like a bug in the API, but your code is a logical workaround (but note the 1000 request/month rate limit, which you might quickly expend doing one name at a time).