Which rate do you want ? Official rates Guild 2:1 rates
Era	Goods	Input	# items	Result
Bronze	Dye, Lumber, Marble, Stone, Wine		0
Iron	Cloth, Ebony, Iron, Jewelry, Limestone		0
Early Middle Age	Alabaster, Copper, Gold, Granite, Honey		0
High Middle Age	Brick, Dried Herbs, Glass, Rope, Salt		0
(*) Late Middle Age	Basalt, Brass, Gunpowder, Silk, Talc Powder		0
(*) Colonial Age	Coffee, Paper, Porcelain, Tar, Wire		0
(*) Industrial Age	Coke, Fertilizer, Rubber, Textiles, Whale oil		0
(*) Progressive Era	Asbestos, Explosives, Gasoline, Machine parts, Tinplate		0
(*) Modern Era	Convenience Food, Feronconcrete, Flavorants, Luxury Materials, Packages		0
(*) Post Modern Era	Genome Data, Industrial Filters, Renewable Resources, Semiconductors, Steel		0
(*) Contemporary Era	Bionics Data, Electromagnets, Gas, Plastics, Robots		0
(*) Tomorrow Era	Nutrition Research, Papercrete, Preservatives, Smart Materials, Translucent Concrete		0
(*) The Future	Algae, Biogeochemical Data, Nanoparticles, Purified Water, Superconductors		0
(*) Arctic Future	A.I. Data, Bioplastics, Nanowire, Paper Batteries, Transester Gas		0
(*) Oceanic Future	Artificial Scales, Biolight, Corals, Pearls, Plankton		0
(*) Virtual Future	Cryptocash, Data Crystals, Golden Rice, Nanites, Tea Silk		0

(*) - Trades from LMA onwards need to be high amouts - 20's / 50's / 100's for the official calculations to be useful. Trades of under 10 items may not display the correct results.

NOTES:

• The official calculations are based on Forge of Empires 'trading' wiki page.
• Most guilds promote a simple 2:1 ratio and 1:1 for same-age goods.