Nasdaq · QSI · stock
Quantum-Si Inc (QSI) stock price history
Every Nasdaq trading session of Quantum-Si Inc from Nov 13, 2020 to Sep 28, 2026: 1,473 daily bars, adjusted for splits and dividends, with minute bars from Jul 13, 2026 forward. The full series is served by the API: a free key covers the last year, paid plans the whole history and minute bars.
QSI adjusted close, 2020 to 2026
- $22.41
- All time high, 2021
- $3.10
- 52 week high, $0.6900 low
- 1,473
- Daily sessions since 2020
Last updated Sep 28, 2026, the last stored session. Refreshes after each trading day. Full 2020 to 2026 series and minute bars.
QSI key facts
- Quantum-Si Inc (QSI) closed at $0.7950 on Sep 28, 2026 on Nasdaq.
- QSI's all time high close is $22.41, set on Feb 18, 2021; its all time low close is $0.6330 on Nov 19, 2024.
- QSI's 52 week range is $0.6900 to $3.10.
- QSI returned -46.6% over the year to Sep 28, 2026 and -91.2% over five years.
- Since Nov 13, 2020 QSI returned -92%, -34.9% a year compounded.
- QSI's deepest drawdown was -97.2% from Feb 18, 2021 to Nov 19, 2024.
- DataCedar holds 1,473 daily sessions of QSI history from Nov 13, 2020 and minute bars from Jul 13, 2026, adjusted for splits and dividends, served by the API under a key.
QSI price chart, 2020 to 2026
QSI returns
Price return from the last close on or before the window start to Sep 28, 2026, on adjusted closes.
| Period | Return |
|---|---|
| 1 month | +1.9% |
| 3 months | -7.0% |
| 6 months | +4.1% |
| Year to date | -28.4% |
| 1 year | -46.6% |
| 3 years | -53.2% |
| 5 years | -91.2% |
| 10 years | n/a |
| Since Nov 13, 2020 | -92.0% |
| Compound annual growth, 5.9 years | -34.9% |
QSI records
Measured on the stored closes; every figure is reproducible from the API series.
- All time high close
- $22.41 on Feb 18, 2021
- All time low close
- $0.6330 on Nov 19, 2024
- 52 week high
- $3.10 on Oct 16, 2025
- 52 week low
- $0.6900 on Jul 30, 2026
- Deepest drawdown
- -97.2% from Feb 18, 2021 to Nov 19, 2024, not yet recovered
- Best single session
- +119.6% on Nov 20, 2024
- Worst single session
- -32.2% on Aug 7, 2023
- Volatility, 1 year annualised
- 85.4%
- Sessions closing higher, 1 year
- 41%
- Best calendar year
- 2024, +34%
- Worst calendar year
- 2022, -77%
QSI price history by year
Open is the first session's open, high and low span the year, close is the last session's close, and the return is close over the previous year's close. 2020 starts on Nov 13, 2020; 2026 runs to Sep 28, 2026.
| Year | Open | High | Low | Close | Return | Volume | Sessions |
|---|---|---|---|---|---|---|---|
| 2026 | $1.15 | $1.34 | $0.6900 | $0.7950 | -27.7% | 799.4M | 185 |
| 2025 | $2.76 | $5.77 | $0.9500 | $1.10 | -59.3% | 2.7B | 250 |
| 2024 | $2.00 | $4.14 | $0.6120 | $2.70 | +34.3% | 1.3B | 252 |
| 2023 | $1.84 | $3.90 | $1.12 | $2.01 | +9.8% | 264.4M | 250 |
| 2022 | $8.06 | $8.31 | $1.72 | $1.83 | -76.7% | 222.7M | 251 |
| 2021 | $10.06 | $25.00 | $5.33 | $7.87 | -22.5% | 245.3M | 252 |
| 2020 | $9.88 | $11.88 | $9.88 | $10.15 | n/a | 185.4K | 33 |
QSI monthly closes, last 12 months
| Month | Month end close | Change |
|---|---|---|
| September 2026 | $0.7950 | +3.8% |
| August 2026 | $0.7660 | +7.6% |
| July 2026 | $0.7120 | -19.5% |
| June 2026 | $0.8850 | -25.6% |
| May 2026 | $1.19 | +21.3% |
| April 2026 | $0.9810 | +26.7% |
| March 2026 | $0.7740 | -19.0% |
| February 2026 | $0.9560 | -15.4% |
| January 2026 | $1.13 | +2.7% |
| December 2025 | $1.10 | -22.0% |
| November 2025 | $1.41 | -34.4% |
| October 2025 | $2.15 | +52.5% |
About the QSI data
Daily bars. 1,473 sessions from Nov 13, 2020 to Sep 28, 2026, one row per Nasdaq trading day with open, high, low, close and volume. Prices are adjusted for splits and cash dividends so the series is comparable across its whole length; the API also serves the raw, split only and dividend only views.
Minute bars. Stored from Jul 13, 2026 forward, most recent session Sep 28, 2026. Minute history is captured from the day collection began and is never backfilled, so this start date is exact. Five minute, fifteen minute and hourly bars are derived from these minutes.
Time and currency. Session dates are Nasdaq trading days; minute timestamps are UTC. Prices are in USD. Volume is shares traded on the session.
Get the data. The REST endpoint returns the daily series as JSON with pagination; a free key serves the last year, Quant and above the full history back to Nov 13, 2020, and minute bars come with the paid windows. It takes timeframe (1Min, 5Min, 15Min, 1Hour, 1Day), adjustment, start and end. See the bars endpoint and authentication, and pricing for the plan windows.
curl "https://api.datacedar.com/v3/stocks/QSI/bars?timeframe=1Day&adjustment=all&limit=50000" \
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Common questions
QSI share price history
