IPO Allotment Probability Calculator
Getting an IPO allotment is not guaranteed even for a correctly placed bid. When more shares are bid for than are on offer, someone has to miss out, and how that is decided depends on the category. Retail applicants go into a computerised draw. Non-institutional (HNI) bids are allotted broadly in proportion to their size.
Enter the subscription of your category, in times, and the number of lots you would bid for. The calculator shows a rough chance of getting at least one lot and the number of lots a bid would get on average. You can fill the subscription from a current IPO, and each IPO's Allotment tab shows the same figures worked out for it.
Last reviewed: 30 October 2026
For example 38 for a category subscribed 38x. Use a figure from the IPO's subscription page.
At 0.14x the category is not oversubscribed, so every valid bid is expected to be allotted in full.
How the numbers are worked out
The subscription is the number of shares bid for divided by the number on offer, so 38x means 38 times as many shares were bid for as were offered.
- Not oversubscribed (1x or less): every valid bid is expected to be allotted in full.
- Retail, above 1x: a computerised draw gives one minimum lot to as many applicants as possible, and bidding for more lots does not help. If every applicant bid for one lot, the chance of getting a lot is 1 ÷ subscription. For 38x that is 1 in 38, about 2.6%. It is a floor, because applicants who bid for several lots reduce the number of applications and rejected bids drop out.
- Non-institutional, above 1x: allotment is broadly proportionate. A bid for k lots receives about k ÷ subscription lots on average, and the chance of at least one lot is about that, capped at 100%. How a part of a lot is settled is set out in the offer document.
What these figures cannot see: how many applicants there really are, how many bids will be rejected, and the exact basis of allotment in the offer document. Read how the IPO allotment lottery works for the full picture, and use the application amount calculator to see which category a bid falls in.
Frequently asked questions
How are IPO shares allotted?
If a category is not oversubscribed, every valid bid in it is allotted in full. If retail bids are more than the shares on offer, a computerised draw gives one minimum lot to as many applicants as possible. In the non-institutional categories, allotment is broadly proportionate to the size of the bid. The offer document describes the exact basis of allotment for each issue.
What does a 38x subscription mean for my chance?
It means bids were placed for 38 times the shares on offer. If every retail applicant had bid for exactly one lot, about 1 in 38 would be allotted, which is about 2.6%. Because some applicants bid for several lots and some bids are rejected, the real chance for a one-lot bid is at least that and often higher.
Does applying for more lots increase my chance in the retail draw?
No. In the retail draw each valid application is one ticket, whatever the number of lots in it. A bigger bid ties up more money without improving the draw. In the non-institutional categories, allotment is broadly proportionate, so a larger bid gets more shares on average.
Why does the result say 'at least' for retail?
Subscription counts bids in shares, not applicants. When applicants bid for several lots, there are fewer applications than the subscription suggests, so each application has a better chance than 1 in N. Rejected bids work the same way. The 1 in N figure is therefore a floor.
What if the category is subscribed less than 1x?
Then there is more on offer than was bid for, and every valid bid is expected to be allotted in full. The figure can change until bidding closes, so check the final subscription.
Does GMP or the listing gain affect allotment?
No. Allotment is decided by the draw or by proportion, using the bids received. GMP is an unofficial price indication and has no part in it.
Can I increase my chances of allotment?
Not by bidding for more lots in the retail category. Each applicant with their own PAN and demat account is a separate application, but several applications from one PAN are not allowed and can be rejected. Whether to apply at all is your decision and this page does not advise on it.