Nasdaq · Common stock
Quantum-Si (QSI)
$1.46 +$0.06 (+4.29%)
- Day’s range
- $1.36–$1.48
- Volume
- 10.3M
QSI price history
QSI closed at $1.46 on Oct. 26, 2026. Over the past year, its daily close ranged from $0.7023 on July 29, 2026 to $2.34 on Oct. 27, 2025.
Data table: QSI daily closes, the past year
| Date | Close |
|---|---|
| Oct. 26, 2026 | $1.46 |
| Oct. 23, 2026 | $1.40 |
| Oct. 22, 2026 | $1.15 |
| Oct. 21, 2026 | $1.23 |
| Oct. 20, 2026 | $1.16 |
| Oct. 19, 2026 | $1.09 |
| Oct. 16, 2026 | $1.12 |
| Oct. 15, 2026 | $1.31 |
| Oct. 14, 2026 | $1.39 |
| Oct. 13, 2026 | $1.41 |
| Oct. 12, 2026 | $1.36 |
| Oct. 9, 2026 | $1.53 |
| Oct. 8, 2026 | $1.22 |
| Oct. 7, 2026 | $1.28 |
| Oct. 6, 2026 | $1.22 |
| Oct. 5, 2026 | $1.28 |
| Oct. 2, 2026 | $1.55 |
| Oct. 1, 2026 | $1.43 |
| Sept. 30, 2026 | $1.07 |
| Sept. 29, 2026 | $0.9581 |
| Sept. 28, 2026 | $0.7950 |
| Sept. 25, 2026 | $0.8343 |
| Sept. 24, 2026 | $0.7850 |
| Sept. 23, 2026 | $0.7587 |
| Sept. 22, 2026 | $0.7847 |
| Sept. 21, 2026 | $0.7559 |
| Sept. 18, 2026 | $0.7451 |
| Sept. 17, 2026 | $0.7700 |
| Sept. 16, 2026 | $0.7301 |
| Sept. 15, 2026 | $0.7200 |
| Sept. 14, 2026 | $0.7250 |
| Sept. 11, 2026 | $0.7400 |
| Sept. 10, 2026 | $0.7391 |
| Sept. 9, 2026 | $0.7500 |
| Sept. 8, 2026 | $0.7600 |
| Sept. 4, 2026 | $0.7660 |
| Sept. 3, 2026 | $0.7610 |
| Sept. 2, 2026 | $0.7610 |
| Sept. 1, 2026 | $0.7573 |
| Aug. 31, 2026 | $0.7659 |
| Aug. 28, 2026 | $0.7800 |
| Aug. 27, 2026 | $0.8031 |
| Aug. 26, 2026 | $0.7906 |
| Aug. 25, 2026 | $0.8473 |
| Aug. 24, 2026 | $0.7693 |
| Aug. 21, 2026 | $0.8350 |
| Aug. 20, 2026 | $0.7800 |
| Aug. 19, 2026 | $0.7701 |
| Aug. 18, 2026 | $0.7280 |
| Aug. 17, 2026 | $0.7442 |
| Aug. 14, 2026 | $0.7398 |
| Aug. 13, 2026 | $0.7900 |
| Aug. 12, 2026 | $0.8374 |
| Aug. 11, 2026 | $0.8202 |
| Aug. 10, 2026 | $0.7901 |
| Aug. 7, 2026 | $0.8144 |
| Aug. 6, 2026 | $0.7550 |
| Aug. 5, 2026 | $0.7565 |
| Aug. 4, 2026 | $0.7654 |
| Aug. 3, 2026 | $0.7460 |
| July 31, 2026 | $0.7124 |
| July 30, 2026 | $0.7200 |
| July 29, 2026 | $0.7023 |
| July 28, 2026 | $0.7606 |
| July 27, 2026 | $0.7834 |
| July 24, 2026 | $0.7701 |
| July 23, 2026 | $0.7900 |
| July 22, 2026 | $0.8000 |
| July 21, 2026 | $0.8360 |
| July 20, 2026 | $0.8170 |
| July 17, 2026 | $0.8224 |
| July 16, 2026 | $0.8193 |
| July 15, 2026 | $0.8620 |
| July 14, 2026 | $0.8662 |
| July 13, 2026 | $0.8693 |
| July 10, 2026 | $0.8827 |
| July 9, 2026 | $0.9624 |
| July 8, 2026 | $0.9127 |
| July 7, 2026 | $0.9195 |
| July 6, 2026 | $0.9517 |
| July 2, 2026 | $0.9304 |
| July 1, 2026 | $0.9241 |
| June 30, 2026 | $0.8850 |
| June 29, 2026 | $0.8889 |
| June 26, 2026 | $0.8548 |
| June 25, 2026 | $0.8573 |
| June 24, 2026 | $0.8272 |
| June 23, 2026 | $0.8800 |
| June 22, 2026 | $0.9212 |
| June 18, 2026 | $0.9990 |
| June 17, 2026 | $0.9443 |
| June 16, 2026 | $0.9540 |
| June 15, 2026 | $0.9885 |
| June 12, 2026 | $0.9467 |
| June 11, 2026 | $0.9730 |
| June 10, 2026 | $0.9465 |
| June 9, 2026 | $0.9871 |
| June 8, 2026 | $1.06 |
| June 5, 2026 | $1.05 |
| June 4, 2026 | $1.28 |
| June 3, 2026 | $1.19 |
| June 2, 2026 | $1.24 |
| June 1, 2026 | $1.18 |
| May 29, 2026 | $1.19 |
| May 28, 2026 | $1.20 |
| May 27, 2026 | $1.13 |
| May 26, 2026 | $1.08 |
| May 22, 2026 | $1.06 |
| May 21, 2026 | $0.9900 |
| May 20, 2026 | $0.8757 |
| May 19, 2026 | $0.8610 |
| May 18, 2026 | $0.8539 |
| May 15, 2026 | $0.8901 |
| May 14, 2026 | $0.9329 |
| May 13, 2026 | $0.9294 |
| May 12, 2026 | $0.9445 |
| May 11, 2026 | $0.9222 |
| May 8, 2026 | $0.9066 |
| May 7, 2026 | $0.9806 |
| May 6, 2026 | $1.03 |
| May 5, 2026 | $0.9613 |
| May 4, 2026 | $0.9715 |
| May 1, 2026 | $0.9582 |
| April 30, 2026 | $0.9806 |
| April 29, 2026 | $0.8648 |
| April 28, 2026 | $0.9120 |
| April 27, 2026 | $0.9003 |
| April 24, 2026 | $0.9058 |
| April 23, 2026 | $0.9406 |
| April 22, 2026 | $1.06 |
| April 21, 2026 | $0.9770 |
| April 20, 2026 | $1.01 |
| April 17, 2026 | $1.07 |
| April 16, 2026 | $1.04 |
| April 15, 2026 | $1.05 |
| April 14, 2026 | $0.8408 |
| April 13, 2026 | $0.7887 |
| April 10, 2026 | $0.7405 |
| April 9, 2026 | $0.7469 |
| April 8, 2026 | $0.7505 |
| April 7, 2026 | $0.7114 |
| April 6, 2026 | $0.7291 |
| April 2, 2026 | $0.7478 |
| April 1, 2026 | $0.7476 |
| March 31, 2026 | $0.7740 |
| March 30, 2026 | $0.7378 |
| March 27, 2026 | $0.7641 |
| March 26, 2026 | $0.8087 |
| March 25, 2026 | $0.8650 |
| March 24, 2026 | $0.8511 |
| March 23, 2026 | $0.8980 |
| March 20, 2026 | $0.8451 |
| March 19, 2026 | $0.8613 |
| March 18, 2026 | $0.8824 |
| March 17, 2026 | $0.9302 |
| March 16, 2026 | $0.9435 |
| March 13, 2026 | $0.9496 |
| March 12, 2026 | $0.9760 |
| March 11, 2026 | $1.05 |
| March 10, 2026 | $1.04 |
| March 9, 2026 | $0.9259 |
| March 6, 2026 | $0.8618 |
| March 5, 2026 | $0.9095 |
| March 4, 2026 | $0.9100 |
| March 3, 2026 | $0.9480 |
| March 2, 2026 | $0.9334 |
| Feb. 27, 2026 | $0.9564 |
| Feb. 26, 2026 | $1.01 |
| Feb. 25, 2026 | $0.9901 |
| Feb. 24, 2026 | $0.9302 |
| Feb. 23, 2026 | $0.9119 |
| Feb. 20, 2026 | $0.9408 |
| Feb. 19, 2026 | $0.9607 |
| Feb. 18, 2026 | $0.9064 |
| Feb. 17, 2026 | $0.9388 |
| Feb. 13, 2026 | $0.9906 |
| Feb. 12, 2026 | $0.9751 |
| Feb. 11, 2026 | $1.04 |
| Feb. 10, 2026 | $1.10 |
| Feb. 9, 2026 | $1.07 |
| Feb. 6, 2026 | $1.07 |
| Feb. 5, 2026 | $0.9321 |
| Feb. 4, 2026 | $1.03 |
| Feb. 3, 2026 | $1.09 |
| Feb. 2, 2026 | $1.10 |
| Jan. 30, 2026 | $1.13 |
| Jan. 29, 2026 | $1.17 |
| Jan. 28, 2026 | $1.20 |
| Jan. 27, 2026 | $1.23 |
| Jan. 26, 2026 | $1.21 |
| Jan. 23, 2026 | $1.25 |
| Jan. 22, 2026 | $1.31 |
| Jan. 21, 2026 | $1.23 |
| Jan. 20, 2026 | $1.19 |
| Jan. 16, 2026 | $1.27 |
| Jan. 15, 2026 | $1.23 |
| Jan. 14, 2026 | $1.27 |
| Jan. 13, 2026 | $1.27 |
| Jan. 12, 2026 | $1.21 |
| Jan. 9, 2026 | $1.22 |
| Jan. 8, 2026 | $1.25 |
| Jan. 7, 2026 | $1.26 |
| Jan. 6, 2026 | $1.28 |
| Jan. 5, 2026 | $1.26 |
| Jan. 2, 2026 | $1.16 |
| Dec. 31, 2025 | $1.10 |
| Dec. 30, 2025 | $1.11 |
| Dec. 29, 2025 | $1.18 |
| Dec. 26, 2025 | $1.23 |
| Dec. 24, 2025 | $1.31 |
| Dec. 23, 2025 | $1.23 |
| Dec. 22, 2025 | $1.27 |
| Dec. 19, 2025 | $1.27 |
| Dec. 18, 2025 | $1.22 |
| Dec. 17, 2025 | $1.20 |
| Dec. 16, 2025 | $1.22 |
| Dec. 15, 2025 | $1.23 |
| Dec. 12, 2025 | $1.29 |
| Dec. 11, 2025 | $1.40 |
| Dec. 10, 2025 | $1.44 |
| Dec. 9, 2025 | $1.42 |
| Dec. 8, 2025 | $1.45 |
| Dec. 5, 2025 | $1.44 |
| Dec. 4, 2025 | $1.47 |
| Dec. 3, 2025 | $1.36 |
| Dec. 2, 2025 | $1.27 |
| Dec. 1, 2025 | $1.29 |
| Nov. 28, 2025 | $1.41 |
| Nov. 26, 2025 | $1.35 |
| Nov. 25, 2025 | $1.35 |
| Nov. 24, 2025 | $1.35 |
| Nov. 21, 2025 | $1.27 |
| Nov. 20, 2025 | $1.24 |
| Nov. 19, 2025 | $1.28 |
| Nov. 18, 2025 | $1.27 |
| Nov. 17, 2025 | $1.30 |
| Nov. 14, 2025 | $1.37 |
| Nov. 13, 2025 | $1.39 |
| Nov. 12, 2025 | $1.52 |
| Nov. 11, 2025 | $1.58 |
| Nov. 10, 2025 | $1.60 |
| Nov. 7, 2025 | $1.58 |
| Nov. 6, 2025 | $1.65 |
| Nov. 5, 2025 | $1.80 |
| Nov. 4, 2025 | $1.84 |
| Nov. 3, 2025 | $2.00 |
| Oct. 31, 2025 | $2.15 |
| Oct. 30, 2025 | $2.03 |
| Oct. 29, 2025 | $2.14 |
| Oct. 28, 2025 | $2.18 |
| Oct. 27, 2025 | $2.34 |
Key figures
- 52-week range
- $0.7023–$2.34Low July 29, 2026; high Oct. 27, 2025
- Average daily volume
- 5.7MPast 3 months
- Market value
- $290.5M
- Dividend yield
- —
- From 52-week high
- −37.61%
Price change
- 1 month
- +75.00%
- 3 months
- +89.59%
- Year to date
- +32.73%
- 1 year
- −36.24%
$1,000 a year ago
$1,000 put into QSI at the close on Oct. 24, 2025 would be worth $638.
Price only, dividends not included.
What Wall Street says about QSI
In the past 90 days, Wall Street firms published 1 rating or price-target action on QSI: 1 reiterated rating.
| Action | Rating | |||
|---|---|---|---|---|
| HC Wainwright & Co. | Reiterates | Buy | $4 |
Ratings and price targets are the firms’ own opinions, reported as published.
Not investment advice.
About Quantum-Si Incorporated Class A Common Stock
Quantum-Si Inc is a life sciences company focused on proteomics research and analytical technologies. It develops single-molecule detection platforms designed to enable next-generation protein sequencing (NGPS) and large-scale protein analysis. Its technology supports massively parallel sequencing of proteins and can also be applied to the study of nucleic acids, providing tools for researchers and clinical applications in molecular analysis. The company's revenue is derived from sales of products and services.
- Headquarters
- Branford, Conn.
- Employees
- 145
- Listed
- June 11, 2021
- Industry
- Measuring & controlling devices, nec
In WallStreetDigest editions
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