Spanx sizing help

Short of a tummy tuck, going to a wedding soon and was going to buy spanx. They come in Small, medium, large. What size for a 12? I am confused! Thank

SPANX Faux Leather Leggings Review + 15% Coupon - Schimiggy

Size Chart Lavender Bow

Spanx Size Chart – Bralissimo

SPANX tights review: Hosiery that'll keep you in check

Size Guide for Clothes – Mayze Online

FAQ Shapewear and Swimwear, Womens Shapewear

Bra Size Calculator – Bras & Honey USA

Spanx Shapewear, from Beige Plus, the Plus Size Boutique

Assets Shaping Tights Textured - Size 3 Diagonal Wave Black Spanx Sara Blakely - Helia Beer Co

Spanx Assets High Waist Shaping Short Shapewear Mid Thigh Control 871B, Size 4