# COI PCR — StockMojo

> Intraday change-in-OI PCR with COI Strength % and Put/Call Dominance signals

- Live page: https://stockmojo.in/change-in-oi-pcr
- Content last updated: 2026-07-14
- Platform: StockMojo — free options analytics for Indian markets (NSE F&O)

This is a machine-readable markdown mirror of the live tool page. The live page shows real-time NSE data during market hours (09:15-15:30 IST) and supports 200+ F&O symbols via per-symbol URLs like https://stockmojo.in/change-in-oi-pcr/banknifty.

## Frequently asked questions

### What is COI PCR (Change in OI PCR)?

COI PCR is the Put-Call Ratio calculated from today's change in open interest instead of total open interest. It divides the intraday change in put OI by the intraday change in call OI, so it reflects only the positions traders are building or unwinding today — not the stale positioning carried from previous sessions.

### How is COI PCR different from the regular PCR?

Regular PCR uses total accumulated open interest, which includes positions built over days or weeks, so it moves slowly. COI PCR uses only today's OI change, so it reacts within minutes to fresh put or call writing. Day traders watch COI PCR to catch sentiment shifts before they show up in the total PCR.

### What is COI Strength % and how is it calculated?

COI Strength % normalizes the put-call imbalance to a bounded scale: ((PE COI − CE COI) / (|PE COI| + |CE COI|)) × 100. The result always sits between −100% and +100%, which avoids the division problems a raw ratio has when OI change is small or negative. OI Strength % applies the same formula to total open interest.

### What do Put Dominance, Neutral and Call Dominance mean?

StockMojo classifies the strength reading into three bands: above +60% is Put Dominance (the put side is much stronger), between −60% and +60% is Neutral (balanced activity), and below −60% is Call Dominance (the call side is much stronger). The badges above the chart show the live classification for both COI and total OI.

### Is Put Dominance bullish or bearish?

In Indian index options, heavy fresh put writing is usually read as bullish — sellers are collecting premium on the bet that support holds. So Put Dominance (strength above +60%) typically supports upside, while Call Dominance (below −60%) signals call writers defending levels overhead, which is bearish. Always confirm with price action before trading the signal.

### Why can COI PCR spike or look extreme early in the session?

In the first minutes of trade the change in call OI can be near zero, so the ratio's denominator is tiny and the reading swings violently. This is inherent to any change-based ratio. The COI Strength % chart solves it — being bounded between −100% and +100%, it stays readable from the opening bell.

### Which strikes are included in the calculation?

You control it. ATM ± Range follows the ATM strike automatically and sums OI across the chosen number of strikes on each side; Strike ± Range anchors the window on a fixed strike; Custom Strikes lets you hand-pick the strikes. A tighter range (ATM ± 5 to ± 10) keeps the reading focused on where the real intraday battle happens.

### Can I see COI PCR for past trading days?

Yes. Switch to Historical mode and pick any past session — the tool rebuilds the full intraday COI PCR, strength bands and change-in-OI lines for that day, with the same expiry and strike-range controls as the live view. Historical access requires a paid plan.

## How to use the StockMojo COI PCR tool

1. **Select an underlying and expiry** — Choose Nifty, BankNifty, Sensex or an F&O stock, then pick the expiry you trade. The nearest weekly expiry carries most of the intraday activity.
2. **Set the strike window** — Start with ATM ± 10 strikes. Use Strike ± Range to anchor a fixed level, or Custom Strikes to isolate specific strikes you are tracking.
3. **Read the COI PCR line** — A rising COI PCR means fresh put writing is outpacing call writing today (supportive); a falling line means call writers are in control.
4. **Check the dominance bands** — On the strength chart, above +60% is Put Dominance, below −60% is Call Dominance, and the middle zone is Neutral. Sharp flips across the zero line often precede intraday trend changes.
5. **Confirm with the Change-in-OI chart** — The PE vs CE change-in-OI lines show which side is actually adding contracts. Confirm a dominance signal against these lines and price action before entering a trade.

## Related tools

- [Put Call Ratio](https://stockmojo.in/put-call-ratio) — markdown: https://stockmojo.in/put-call-ratio.md
- [PCR Trend](https://stockmojo.in/pcr-trend) — markdown: https://stockmojo.in/pcr-trend.md
- [PE-CE Difference](https://stockmojo.in/pe-ce-difference) — markdown: https://stockmojo.in/pe-ce-difference.md

## Glossary

Terms used: put-call-ratio, open-interest. Definitions: https://stockmojo.in/glossary