The women's 800 metres at the 2021 World Athletics U20 Championships was held at the Kasarani Stadium from 19 to 21 August.
Results.
Heats.
Qualification: First 3 of each heat (Q) and the 4 fastest times (q) qualified for the semifinals.
Semifinals.
Qualification: First 3 of each heat (Q) and the 2 fastest times (q) qualified for the final.
Final.
The final was held on 21 August at 16:46.
References.
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