Anna Karolina Schmiedlova began playing at age 7 when her parents introduced her to the sport. She decided she wanted to take it more seriously when she became the Under 12 No.1 in Slovakia. A former Roland Garros junior finalist in 2012 (l. Beck), she made her Grand Slam debut as a qualifier in 2013 in Paris, losing in the first-round. After Wimbledon, she reached the final at $100k ITF event in Biarritz (l. Vogt) and became the 15th Slovak woman to climb into the Top 100 at No.97.
At 2014 Roland Garros she upset Venus Williams to reach the third-round for the first time in a major (l.Muguruza). At ITF level she won her biggest title at $75k event in Trnava (d. Strycova) and lost the $100k ITF final in Prague to Watson).
In 2015, her breakthrough season, she reached her first WTA final in Rio (l. Errani). After putting on an inspired performance to beat No.1 seed Agnieszka Radwanska in the semifinals, she won her first WTA title in Katowice (d. Giorgi in the final). She claimed her second title in Bucharest (d. Errani) and reached two quarter-finals at WTA Premier 5-level in Cincinnati (l.Jankovic) and Wuhan (l. Muguruza). She also moved to the third-round at Us Open and qualified for the WTA Elite Trophy in Zhuhai where she claimed her maiden Top 10 win over Roberta Vinci, losing just one game. She finished the season at No.26.
In 2016, however, she went on a losing streak of 16 WTA tour-level matches and saw her ranking plummet from the Top 30 to outside the world's Top 200.
She managed to end 2017 ranked No.133. She posted an 11-match winning streak on the ITF Circuit from the end of May through mid-June, winning two $25k titles in Grado and Stare Splavy, without the loss of a set. She finished the season with her biggest title in two years, at ITF level, in the $80k event on the campus of Mercer University in the last week of October (d. Duval in the final).