What does it cost to level Engineering right now?

11.8kg in reagents at today's KR auction prices, over about 131 crafts. Sell the results and it comes back to 11.8kg.

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 16:27 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 Engineering · KR · prices as of 16:27 UTC

Engineering leveling 1 → 75 · Cataclysm Engineering

11.8kg in reagents over about 131 crafts. Sell what you make and it comes back to 11.8kg.

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

Elementium Bar×14048

6,720

×1406,720

Handful of Obsidium Bolts×3549

Total11,760

Step 1 · Skill 1 → 25

Yellow→Green

Grounded Plasma Shield

trainer

About 64 crafts.575

per skill point23

Tinker's Kit×64

Step 2 · Skill 25 → 40

Orange→Green

Electrified Ether

trainer

About 32 crafts.1,280

per skill point85

Volatile Air×64

Step 3 · Skill 40 → 75

Orange

Heat-Treated Spinning Lure

trainer

About 35 crafts.9,905

per skill point283

Handful of Obsidium Bolts×35

Elementium Bar×140

Volatile Fire×35

Skill 75 — done. Now sell what you made.

Crafted itemUnitsEachTotal

Electrified Ether3223

327

Heat-Treated Spinning Lure7062

7043

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

Back in your pocket11,752

What's worth crafting with Engineering right now

Questions

How this route is built

What does it cost to level Engineering right now?: 11.8kg in reagents at today's KR auction prices, over about 131 crafts. Sell the results and it comes back to 11.8kg.
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 16:27 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.