OSRS Giants' Foundry Calculator
Convert a reputation target into complete swords and an estimated session duration using your own observed reward and pace.
Set activity assumptions
Estimated swords
136 estimated minutes.
How it works
This is a reputation-and-time ledger, not a quality simulator: it converts a reputation gap into completed commissions, then into minutes at your own pace.
Mechanics assumptions this page makes
The minigame is unlocked by the Sleeping Giants quest and needs 15 Smithing. A commission is a fixed sequence: load bars into the crucible, pour the alloy into your chosen mould, work the blade at the grindstone, trip hammer and polishing wheel while its heat stays inside each station’s band, then hand it in. Reputation and Smithing experience are paid once, at hand-in, and scale with the quality reached and the alloy poured — both player decisions, so the tool asks for the reputation a representative sword actually gave you.
Bar cost and Smithing experience sit outside the model; use the Smithing skill calculator when experience is the goal.
How reputation per sword moves the plan
The table holds a 2,000-reputation gap fixed and varies only the reward observed per commission.
| Reputation per sword | Swords for a 2,000 gap | Minutes at 8 min/sword |
|---|---|---|
| 80 | 25 | 200 |
| 100 | 20 | 160 |
| 120 | 17 | 136 |
| 150 | 14 | 112 |
| 200 | 10 | 80 |
Interpretation thresholds
Three thresholds decide whether a plan is realistic. The ceiling: a fraction of a sword costs a whole sword, so a 16.7-commission gap costs 17. Pace: at eight minutes a sword an hour buys 7.5 hand-ins. Sensitivity: sword count moves as the reciprocal of reputation per sword, so a 20% better average removes about a sixth of the remaining commissions while a 20% worse average adds about a quarter. If your observed reward swings more than roughly 15% between swords, plan with the lower figure.
Worked example
From 1,000 to 3,000 reputation at 120 per sword requires 17 completed swords, because 2,000 ÷ 120 is 16.67 and a partial commission pays nothing; at eight minutes each, budget about 136 minutes. Second worked example: a smith at 3,400 reputation aiming for 8,000 who averages 155 per sword needs ⌈4,600 ÷ 155⌉ = 30 swords, or 195 minutes at 6.5 minutes each. Averaging 120 instead turns the same gap into 39 swords and about 254 minutes.
Interpreting the result
Start by checking that each field describes the same scenario as the result: levels are visible base levels, bonuses are entered separately, costs are per unit, and a one-in-X rate means one divided by X on each eligible roll. The calculator updates immediately and writes the complete input state into the address bar. “Copy link” preserves those assumptions; “Copy result” copies a short summary rather than the entire method.
Do not treat a rounded count as an hourly rate. A required-action total says how many successful units complete the target under the entered reward. Banking, movement, failed attempts, animation timing, missed ticks and setup changes affect elapsed time. When time matters, measure a representative session with the same method and divide the required count by the observed successful actions per hour.
Economic outputs are arithmetic scenarios rather than live market quotations. Check current item values before buying supplies, include any outputs that can be sold, and consider limits or low-volume price movement. Probability outputs describe repeated independent trials; they do not promise that a result arrives at the displayed attempt count. The visible formula is the authority for what this page includes.
Read this as a planning estimate. Game updates, equipment effects, failures, travel, downtime and live prices can move a real session away from the mathematical result. Check the inputs against the account and use the output as a reproducible baseline.
Questions about OSRS Giants' Foundry Calculator
Which alloy is best?
Why are swords rounded up?
Is Smithing XP included?
What do I need before starting a Giants' Foundry commission?
Why does my reputation per sword change between commissions?
Does the estimate include bar cost or Smithing XP?
Sources
Mechanics and fixed tables were reviewed in 2026. Price-like inputs are user-controlled or approximate rather than live quotes. Source links name the public reference used for the page; the visible formula states the exact implementation.
- Old School RuneScape Wiki — Giants' Foundry — Commission sequence, crucible and mould handling, heat-band stations, and the quality-scaled reward at hand-in, reviewed 2026.
- Old School RuneScape Wiki — Sleeping Giants — Quest that unlocks the minigame, and the 15 Smithing entry requirement, reviewed 2026.
- Old School RuneScape Wiki — Smithing — Skill context for the experience side of a commission, reviewed 2026.