Quantum-Si incorporated (QSI) Stock Price History
Historical prices from 2020 to 2026
- 1M
- +84.5%
- 3M
- +77.2%
- YTD
- +20.7%
- 1Y
- -36.4%
- 3Y
- +3.6%
- 5Y
- -30.0%
Loading 10-year price history...
QSI Historical Performance
QSI Annual Returns
Year-by-year price performance · 2020–2026
- 2020 annual price return
- +2.7%
- 2021 annual price return
- -25.0%
- 2022 annual price return
- -77.7%
- 2023 annual price return
- +9.2%
- 2024 annual price return
- +33.0%
- 2025 annual price return
- -74.2%
- 2026 annual price return
- +31.9%
QSI Stock Price Trajectory (2020–2026)
As of October 24, 2026, Quantum-Si incorporated (QSI) trades at $1.40, representing a -36.4% return over the past year. The stock has delivered a -83.2% total return over five years (-30.0% CAGR), reflecting challenging market conditions.
The stock reached its all-time high of $25.00 on February 18, 2021. From this peak, QSI has corrected -94.4%, currently trading 47% above its 200-day moving average, indicating continued institutional support.
When compared to Healthcare sector peers PACB (+8.2% 1Y), CDNA (+370.8% 1Y), and ACMR (+25.6% 1Y), QSI has underperformed the peer group average. Compare QSI vs PACB →
QSI Historical Price Data · from 2020
Rows 1–50 of 1,492| Date | Open | High | Low | Close | Volume | Change % |
|---|---|---|---|---|---|---|
| 2026-10-23 | 1.16 | 1.42 | 1.15 | 1.40 | 11.39M | +21.74% |
| 2026-10-22 | 1.17 | 1.21 | 1.15 | 1.15 | 3.57M | -6.50% |
| 2026-10-21 | 1.16 | 1.23 | 1.16 | 1.23 | 3.42M | +6.03% |
| 2026-10-20 | 1.06 | 1.20 | 1.04 | 1.16 | 6.18M | +6.42% |
| 2026-10-19 | 1.15 | 1.15 | 1.01 | 1.09 | 8.71M | -2.68% |
| 2026-10-16 | 1.33 | 1.33 | 1.10 | 1.12 | 7.69M | -14.50% |
| 2026-10-15 | 1.35 | 1.39 | 1.24 | 1.31 | 9.27M | -5.76% |
| 2026-10-14 | 1.34 | 1.44 | 1.33 | 1.39 | 5.36M | -1.42% |
| 2026-10-13 | 1.35 | 1.46 | 1.31 | 1.41 | 6.24M | +3.68% |
| 2026-10-12 | 1.48 | 1.48 | 1.34 | 1.36 | 10.36M | -11.11% |
| 2026-10-09 | 1.26 | 1.66 | 1.26 | 1.53 | 40.90M | +25.41% |
| 2026-10-08 | 1.29 | 1.30 | 1.20 | 1.22 | 5.85M | -4.69% |
| 2026-10-07 | 1.17 | 1.31 | 1.09 | 1.28 | 8.04M | +4.92% |
| 2026-10-06 | 1.29 | 1.41 | 1.19 | 1.22 | 8.70M | -4.69% |
| 2026-10-05 | 1.53 | 1.53 | 1.26 | 1.28 | 19.19M | -17.42% |
| 2026-10-02 | 1.39 | 1.55 | 1.17 | 1.55 | 18.77M | +8.39% |
| 2026-10-01 | 1.20 | 1.48 | 1.15 | 1.43 | 33.06M | +33.64% |
| 2026-09-30 | 0.96 | 1.12 | 0.96 | 1.07 | 13.84M | +11.68% |
| 2026-09-29 | 0.81 | 1.03 | 0.81 | 0.96 | 23.01M | +20.52% |
| 2026-09-28 | 0.82 | 0.83 | 0.80 | 0.80 | 1.57M | -4.71% |
| 2026-09-25 | 0.79 | 0.84 | 0.78 | 0.83 | 2.59M | +6.28% |
| 2026-09-24 | 0.75 | 0.80 | 0.74 | 0.79 | 1.59M | +3.47% |
| 2026-09-23 | 0.79 | 0.81 | 0.75 | 0.76 | 1.48M | -3.31% |
| 2026-09-22 | 0.76 | 0.79 | 0.75 | 0.78 | 2.43M | +3.81% |
| 2026-09-21 | 0.76 | 0.77 | 0.75 | 0.76 | 1.13M | +1.45% |
| 2026-09-18 | 0.79 | 0.80 | 0.74 | 0.75 | 1.71M | -3.23% |
| 2026-09-17 | 0.75 | 0.80 | 0.75 | 0.77 | 2.83M | +5.47% |
| 2026-09-16 | 0.72 | 0.75 | 0.72 | 0.73 | 915K | +1.40% |
| 2026-09-15 | 0.72 | 0.74 | 0.72 | 0.72 | 1.17M | -0.69% |
| 2026-09-14 | 0.73 | 0.75 | 0.72 | 0.72 | 1.39M | -2.03% |
| 2026-09-11 | 0.74 | 0.76 | 0.74 | 0.74 | 1.07M | +0.12% |
| 2026-09-10 | 0.75 | 0.76 | 0.73 | 0.74 | 1.72M | -1.45% |
| 2026-09-09 | 0.76 | 0.77 | 0.75 | 0.75 | 1.45M | -1.32% |
| 2026-09-08 | 0.77 | 0.79 | 0.76 | 0.76 | 1.05M | -0.78% |
| 2026-09-04 | 0.76 | 0.77 | 0.76 | 0.77 | 899K | +0.66% |
| 2026-09-03 | 0.77 | 0.79 | 0.76 | 0.76 | 980K | 0.00% |
| 2026-09-02 | 0.76 | 0.79 | 0.75 | 0.76 | 1.62M | +0.49% |
| 2026-09-01 | 0.75 | 0.78 | 0.75 | 0.76 | 1.50M | -1.12% |
| 2026-08-31 | 0.78 | 0.78 | 0.76 | 0.77 | 1.13M | -1.81% |
| 2026-08-28 | 0.82 | 0.82 | 0.77 | 0.78 | 2.42M | -2.88% |
| 2026-08-27 | 0.79 | 0.83 | 0.79 | 0.80 | 1.38M | +1.58% |
| 2026-08-26 | 0.85 | 0.85 | 0.79 | 0.79 | 2.66M | -6.69% |
| 2026-08-25 | 0.79 | 0.86 | 0.78 | 0.85 | 4.37M | +10.14% |
| 2026-08-24 | 0.80 | 0.83 | 0.75 | 0.77 | 3.85M | -7.87% |
| 2026-08-21 | 0.78 | 0.93 | 0.78 | 0.83 | 7.83M | +7.05% |
| 2026-08-20 | 0.77 | 0.81 | 0.77 | 0.78 | 3.23M | +1.29% |
| 2026-08-19 | 0.72 | 0.78 | 0.72 | 0.77 | 2.86M | +5.78% |
| 2026-08-18 | 0.73 | 0.74 | 0.72 | 0.73 | 1.52M | -2.18% |
| 2026-08-17 | 0.74 | 0.80 | 0.74 | 0.74 | 2.43M | +0.59% |
| 2026-08-14 | 0.75 | 0.77 | 0.71 | 0.74 | 7.00M | -6.35% |
QSI Chart Terminal
Live VCP patterns, Cup & Handle overlays, support/resistance, and AI trade plans.
Live Breakouts Feed
High-probability breakout stocks crossing their pivot across 5 pattern engines.
Intrinsic Valuation
DCF models, multiple analysis, and analyst estimates.
Historical Returns
10-year return with dividends reinvested.
Peer Comparison
Compare growth, multiples, and margins vs sector.
QSI — Frequently Asked Questions
Quick answers to the most common questions about buying QSI stock.
How has QSI stock performed recently?
QSI declined -36.4% over the past year, below its 5-year annualized CAGR of -30.0%. The stock trades above its 200-day moving average, reflecting the downtrend.
What is QSI's all-time high price?
Quantum-Si incorporated reached $25.00 on 2021-02-18. The 52-week high is $2.44. Current 1-year return of -36.4% places the stock further from historical peaks.
Where can I download QSI historical price data?
This page provides QSI daily OHLCV data with 50-day MA, 200-day MA, and RSI indicators. Data spans 2020-2026, downloadable in CSV format.