OSRS ToA Loot Calculator
Team and personal purple odds from real reward points - then the invocation level where your purple per hour stops rising.
Most Tombs of Amascut calculators answer "what is my purple chance" with a flat rate that is wrong above 310 invocation. The useful question is different: where should I stop raising the raid level? Higher invocations buy a better points-to-purple conversion but cost clear time and deaths. This page prices both sides with the Wiki chest formula and your own clear time.
Raid setup
model v1.0 Enter your run to see the odds.
Team sees a purple
1 in 5.63
The purple is yours
1 in 11.3
Your contribution share:
Your target drop
Named item chance already includes your purple rate and the item's share of the purple table. Cumulative runs assume independent raids - going dry never becomes "due".
Expected value at the chest
Default prices are the last-reviewed GE values in the raid model, so the numbers above are a floor you can compare against. The page swaps in live GE mids from the OSRS Wiki API when it loads; value assumes you sell the unique and keeps the standard chest estimate separate.
Team size: who actually gains? ToA scales the team roll by total points, and your share is proportional to contribution. With equal points, team size is close to neutral for your personal chance until the team hits the 55% cap - then extra players dilute you.
| Team | Team points | Team purple | Your share | Your purple | Personal rate | Status |
|---|---|---|---|---|---|---|
| 1 | 40,000 | 8.89% | 100.0% | 8.89% | 1 / 5.6 hrs | equal share |
| 2 | 80,000 | 17.78% | 50.0% | 8.89% | 1 / 5.6 hrs | equal share |
| 3 | 120,000 | 26.67% | 33.3% | 8.89% | 1 / 5.6 hrs | equal share |
| 4 | 160,000 | 35.56% | 25.0% | 8.89% | 1 / 5.6 hrs | equal share |
| 5 | 200,000 | 44.44% | 20.0% | 8.89% | 1 / 5.6 hrs | equal share |
| 6 | 240,000 | 53.33% | 16.7% | 8.89% | 1 / 5.6 hrs | equal share |
| 7 | 280,000 | 55.00% | 14.3% | 7.86% | 1 / 6.4 hrs | team cap |
| 8 | 320,000 | 55.00% | 12.5% | 6.88% | 1 / 7.3 hrs | team cap |
Where the invocation curve peaks
Higher raid level raises the purple rate but lengthens the raid. This curve holds your points and team size fixed and prices the clear time you set below, so the peak is the level where those two forces cancel out for your group.
The rate only falls as the raid level climbs: with points held flat, a 150 level raid clearing in 14.3 min beats the slower high-level runs at 0.22 purple/hr — one purple every 4.5 hrs. Raise the level only if it also raises your points.
| Raid level | Team purple | Your purple | Est. clear | Personal rate |
|---|---|---|---|---|
| 150 | 10.67% | 5.33% | 14.3 min | 0.22 purple/hr |
| 175 | 11.43% | 5.71% | 16.9 min | 0.20 purple/hr |
| 200 | 12.31% | 6.15% | 19.5 min | 0.19 purple/hr |
| 225 | 13.33% | 6.67% | 22.1 min | 0.18 purple/hr |
| 250 | 14.55% | 7.27% | 24.8 min | 0.18 purple/hr |
| 275 | 16.00% | 8.00% | 27.4 min | 0.18 purple/hr |
| 300 | 17.78% | 8.89% | 30.0 min | 0.18 purple/hr |
| 325 | 19.05% | 9.52% | 32.6 min | 0.18 purple/hr |
| 350 | 19.83% | 9.92% | 35.3 min | 0.17 purple/hr |
| 375 | 20.69% | 10.34% | 37.9 min | 0.16 purple/hr |
| 400 | 21.62% | 10.81% | 40.5 min | 0.16 purple/hr |
| 425 | 22.64% | 11.32% | 43.1 min | 0.16 purple/hr |
| 450 | 23.30% | 11.65% | 45.8 min | 0.15 purple/hr |
| 475 | 23.88% | 11.94% | 48.4 min | 0.15 purple/hr |
| 500 | 24.49% | 12.24% | 51.0 min | 0.14 purple/hr |
How the ToA purple roll actually works
You start a raid with 5,000 reward points. Room points are earned from damage, capped at 20,000 per room and 64,000 in total. At the chest the 5,000 start is removed, and the remaining points buy purple chance at 1% per (10,500 - 20 × scaled raid level) points. Raid level is compressed above 310 so each extra invocation buys less:
scaled RL = RL for 0-310 · 310 + (RL - 310)/3 for 311-430 · 350 + (RL - 430)/6 above 430
| Raid level | Scaled RL | Points per 1% | Team chance at 40,000 points |
|---|---|---|---|
| 150 | 150.0 | 7,500 | 5.33% |
| 200 | 200.0 | 6,500 | 6.15% |
| 300 | 300.0 | 4,500 | 8.89% |
| 400 | 340.0 | 3,700 | 10.81% |
| 500 | 361.7 | 3,266.667 | 12.24% |
The team roll is capped at 55%. A purple goes to one player, chosen in proportion to contribution, so with equal points your personal chance is the team chance divided by team size. Deaths remove 20% of your current points with a 1,000 point floor.
40,000 points is the post-start figure (45,000 earned). It is an illustration, not a target - enter your own chest value above.
Why the invocation curve peaks
Purple chance per raid rises with raid level, but raids per hour falls. Multiply them and the result is hump-shaped: the first invocations are nearly free, the middle ones are a fair trade, and the last hundred cost more time than they return. The peak is not a universal number - it depends on your team's execution, gear and deaths.
Set the clear-time penalty on the calculator to match your group. A team that clears 500s almost as fast as 300s should farm 500s; a team that adds ten minutes and two deaths per hundred invocations will usually find the peak near 300. That is the decision the flat-rate calculators cannot answer.
ToA unique split at 300 and 500
Higher raid levels also shift the item table: Osmumten's fang and the Lightbearer lose relative weight, while the Masori pieces and Tumeken's shadow gain. Shares below are per purple, not per raid.
| Item | Share at 300 | Share at 500 | One purple in (500) |
|---|---|---|---|
| Osmumten's fang | 29.2% | 18.2% | 1 in 5.50 |
| Lightbearer | 29.2% | 21.2% | 1 in 4.71 |
| Elidinis' ward | 12.5% | 18.2% | 1 in 5.50 |
| Masori mask | 8.3% | 12.1% | 1 in 8.25 |
| Masori body | 8.3% | 12.1% | 1 in 8.25 |
| Masori chaps | 8.3% | 12.1% | 1 in 8.25 |
| Tumeken's shadow | 4.2% | 6.1% | 1 in 16.5 |
Between the published anchors (150-300, 350, 400, 450, 500) the shares are interpolated. Values between anchors are therefore an approximation of a table that only exists at those levels.
What this model does not claim
- No out-of-bracket unlocks. Some uniques are level-gated; rolling one outside its bracket triggers an extra 1/50 check. We do not model that roll, so low-level pages can slightly understate those items.
- No MVP bonus. The 300 × team size MVP bonus is real but depends on who tops each room, which we cannot know from a planning input.
- Common loot is an estimate. The three standard rolls scale with points and raid level; we use a flat 300K gp placeholder so the per-hour figure stays honest about being approximate.
- No tertiary rolls. Thread of Elidinis, keris jewels and the pet are separate mechanics and are excluded from the GP model.
Model v1.0 · reviewed 2026-11-09 · source: OSRS Wiki chest page (point formula and per-purple table). This is the formula the Wiki documents; calculators that quote a flat 1/10 or 10,500 points per 1% disagree with each other and with the chest page.
ToA loot FAQ
What is the ToA purple rate at raid level 300?
There is no single number, because the roll is driven by points. At raid level 300 the rate is 1% per 4,500 reward points after the 5,000 starting points are removed, so a solo finishing with 45,000 points has about 8.9% for the team. The calculator above uses your real points instead of assuming a fixed rate.
Is 400 invocation better than 300 for purples?
Per raid, yes. Raid level is compressed above 310: 400 counts as 340, which lowers the cost of 1% from 4,500 to 3,700 points. Per hour it depends on how much longer the raid takes and how often you die. The invocation curve on this page holds your points constant and prices your own clear time, so it shows where the trade turns over for your group.
How much does a death cost in ToA?
Each death removes 20% of your current reward points, with a minimum loss of 1,000 points. Points are what buy purple chance, so a death in the last room is far more expensive than the same mistake early. The calculator applies the penalty before removing the 5,000 starting points.
Does a bigger ToA team increase my purple chance?
Usually not. The team's chance scales with total points, and your share is proportional to your contribution, so with equal points your personal chance stays roughly flat as you add players. It only changes when the team hits the 55% unique cap, after which extra players dilute your share.
Why does this disagree with other ToA calculators?
Many calculators use a flat base rate such as 1/10 or 10,500 points per 1% without the raid-level compression. Both are wrong at high invocations. This page follows the Wiki chest formula: 1% per (10,500 - 20 x scaled raid level) points, capped at 55% for the team, with your share set by contribution.
Keep going
Bring your actual kill speed from the DPS calculator into the clear-time field, then price the drop in live GE prices. If you are still deciding between ToA and the new raid, the Fractured Archive loot calculator uses the same engine with contribution-based team rolls.