What does it cost to level Leatherworking right now?

40.1kg in reagents at today's TW auction prices, over about 84 crafts. Sell the results and it comes back to 40.1kg.

Where do these numbers come from?

The skill thresholds are read from the game client data for build 12.1.0.68914. The prices are the region-wide auction house, refreshed every few minutes; these are the snapshot taken at 17:54 UTC.

Why does the route change when I reload?

Because the prices did. The cheapest recipe for a stretch of skill is whichever one's reagents are cheapest at that moment, and that moves through the day.

Profession leveling · Cataclysm Leatherworking · TW · prices as of 17:54 UTC

Leatherworking leveling 1 → 75 · Cataclysm Leatherworking

40.1kg in reagents over about 84 crafts. Sell what you make and it comes back to 40.1kg.

Start skill

Trainer recipes only

Recipe names carry the colour the profession window gives them: orange is a point every craft, yellow is three in four, green is one in four.

Before the first craft — buy it all at once

One trip to the auction house. Vendor lines are cheaper from the profession vendor than from the board.

ReagentNeedEachTotal

Blackened Dragonscale×150018

Blackened Dragonscale Fragment×1101

169

×110169

Total40,124

Step 1 · Skill 1 → 5

Yellow→Green

Blackened Dragonscale

trainer

About 11 crafts.169

per skill point42

Blackened Dragonscale Fragment×110

Step 2 · Skill 5 → 37

Orange→Yellow

Heavy Savage Leather

needs the recipe item

About 33 crafts.8,261

per skill point258

Savage Leather×165

Step 3 · Skill 37 → 45

Orange→Yellow

Twilight Leg Armor

needs the recipe item

About 10 crafts.4,603

per skill point575

Savage Leather×60

Volatile Water×40

Step 4 · Skill 45 → 75

Orange

Twilight Dragonscale Cloak

needs the recipe item

About 30 crafts.27,090

per skill point903

Blackened Dragonscale×1500

Skill 75 — done. Now sell what you made.

Crafted itemUnitsEachTotal

Blackened Dragonscale111

1111

Heavy Savage Leather334

331

Twilight Dragonscale Cloak3046

3013

Twilight Leg Armor0/100

0/100

Capped at what the market takes in 3 days, so a route never pretends to sell hundreds at once.

Back in your pocket40,111

What's worth crafting with Leatherworking right now

Questions

How this route is built

What does it cost to level Leatherworking right now?: 40.1kg in reagents at today's TW auction prices, over about 84 crafts. Sell the results and it comes back to 40.1kg.
Where do these numbers come from?: The skill thresholds are read from the game client data for build 12.1.0.68914. The prices are the region-wide auction house, refreshed every few minutes; these are the snapshot taken at 17:54 UTC.
Why does the route change when I reload?: Because the prices did. The cheapest recipe for a stretch of skill is whichever one's reagents are cheapest at that moment, and that moves through the day.

A first craft pays Knowledge, not skill, so it is shown as a badge and left out of the craft count. Vendor reagents are priced at the lower of the vendor and the auction house.