It would be helpful to have a bit more to go on - your preferred style? a long list? Existing siblings?
Here's a total mix of names:
Solidly popular/traditional:
Abigail, Amy, Bryony, Bethany, Charlotte, Chloe, Elizabeth, Eleanor, Emma, Emily, Felicity, Fiona, Georgia, Grace, Hannah, Holly, Imogen, Isabel, Jessica, Jasmine, Katherine, Katie, Lucy, Leah, Madeleine, Matilda, Natasha, Natalie, Olivia, Phoebe, Rebecca, Rachel, Sophie, Sarah, Thea, Tamsin, Victoria, Zoe
Elegant/European:
Aurelia, Alexandra, Cassandra, Celest, Dorothea, Evangeline, Ellianna, Florence, Francesca, Gloria, Giselle, Genevieve, Gabriella, Hermione, Henrietta, Isabella, Joanna, Juliana, Lydia, Louisa, Miranda, Maria, Natalia, Ophelia, Octavia, Philippa, Paloma, Rosanna, Sophia, Serena, Tabitha, Tallulah, Vanessa, Verity, Zara
Contemporary:
Amaya, Ariel, Bronte, Briar, Cleo, Coco, Darcey, Dana, Effie, Eden, Freya, Halle, Hadley, India, Juno, Juniper, Kiki, Keltie, Livia, Leonie, Maia, Mia, Nyah, Nia, Paige, Piper, Remi, Romilly, Saffron, Sorrel, Tegan, Tilly, Willow, Zia
American:
Aspen, Addison, Avery, Aubrey, Brooke, Bailey, Colby, Dakota, Dylan, Fallon, Harlow, Harley, Kinsley, Kennedy, Kendall, London, Morgan, Macie, Madison, Mackenzie, Nevaeh, Payton, Paisley, Quinn, Riley, Reagan, Sutton, Spencer, Taylor
Celtic/Welsh/Cornish
Aoife, Ailsa, Arwen, Aven, Bronwen, Caoimhe, Caitlin, Ciara, Damaris, Eilidh, Iona, Ishbel, Isobel, Kayleigh, Karensa, Myfanwy, Morven, Nesta, Niamh, Orlaith, Rhiannon, Rhiannyd, Renee, Sian, Sorcha, Sinead, Siobhan
Old Fashioned:
Agnes, Annie, Beatrice, Clara, Cara, Daphne, Dorothy, Elsie, Edith, Esme, Enid, Faith, Frances, Greta, Hazel, Heidi, Ivy, Isla, Iris, Josie, Jessie, Lily, Mary, Martha, Margaret, Maria, Maisy, Nancy, Nellie, Pearl, Polly, Peggy, Queenie, Ruby, Rose, Rita, Sylvia, Sally, Theresa, Tessa, Verity, Winifred
Unusual/Fancy:
Araminta, Amberley, Clarissa, Cassiopeia, Calliope, Delphi, Elisaveta, Evadne, Fenella, Fabia, Georgiana, Giovanna, Heniretta, Isolde, Julianna, Jocasta, Jacinta, Katherina, Keziah, Lorelai, Larissa, Mirabelle, Meredith, Ondine, Perspehone, Pandora, Ramona, Rosina, Rowena, Saskia, Tassita, Talitha, Vashti, Xanthe, Xanthippe, Zipporah