Quantum-Si Incorporated (QSI)

NASDAQ

$0.96

$+0.17

(+20.79%)

After-Hours

Quantum-Si Incorporated (QSI) Live Price Chart

Last updated: ⁦2026-09-29 21:09:20⁩. Prices reflect the latest after-hours trading data. Stock price data is sourced from Massive.

Summary

Quantum-Si Incorporated (QSI) operates in the MEASURING & CONTROLLING DEVICES, NEC sector and is listed on NASDAQ. The stock is currently priced at $0.96, with a market capitalization of $174.01M and a P/E ratio of --. Over the past 52 weeks, its price has ranged from $0.69 to $3.10. This page covers its latest market performance, valuation, price trends and company information.

Key Market Data

Market Cap	$174.01M
Open	$0.81
Day's High	$14.17
Day's Low	$0.61
Previous Close	$0.80
Volume	22.73M
Average Volume	2.52M
P/E Ratio	--
52-Week High	$3.10
52-Week Low	$0.69
Dividend Yield	--
Earnings Date	--

Quantum-Si Incorporated (QSI) After-Hours Stock Price

Quantum-Si Incorporated (QSI) is trading at $0.97 in after-hours trading as of 2026-09-29 21:07:00, up 21.64% ($0.17) from the regular-session close of $0.80.

After-hours trading shows how investors are pricing QSI after the regular session closes. The current after-hours price is above the regular-session close, indicating positive after-hours sentiment.

Quantum-Si Incorporated (QSI) 7-Day Stock Price Change

Over the past seven days, Quantum-Si Incorporated (QSI) moved from $0.76 to $0.96, representing a gain of 27.40% ($0.21).

The stock traded between $0.74 and $1.03 during the period. The latest price is near the upper end of the 7-day range, indicating strong upward.

The average daily volume was 1.54 million shares, down versus the previous seven-day period, indicating lower trading activity.

QSI 52-Week Price Position

Position in Range: 11.3%

52W Low$0.69

52W High$3.10

QSI is currently trading at $0.96, placing it 11.3% of the way from its 52-week low of $0.69 to its 52-week high of $3.10. This percentage reflects the stock's relative position within its 52-week trading range, not its valuation or future performance.

What is Quantum-Si Incorporated (QSI)?

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.

Quantum-Si Incorporated Information

Industry	MEASURING & CONTROLLING DEVICES, NEC
Employees	145
Exchange	NASDAQ
Company Website	https://www.quantum-si.com

How to Buy Quantum-Si Incorporated (QSI) Stock on MEXC

Eligible investors can buy real shares of Quantum-Si Incorporated (QSI) through MEXC RealStocks. Follow these three steps to open a RealStocks account, transfer USDT, and place a US stock order.

Step 1: Open and Verify Your RealStocks Account

Log in to the MEXC App, go to Trade → RealStocks, and select Open Account. Complete the required account-opening and identity verification process with MEXC's partner licensed broker.

Step 2: Transfer USDT to Your RealStocks Account

Go to Wallets → RealStocks and transfer USDT from your Spot Account to your RealStocks Account. RealStocks are quoted in USD, while account funding can be completed using USDT.

Step 3: Search for QSI and Place Your Order

Open the RealStocks trading page and search for QSI. Select a market or limit order, enter the price and quantity as required, review the order details, and submit your order. Once filled, the corresponding real shares will be held in your RealStocks Account.

Frequently Asked Questions (FAQ)

1.What is Quantum-Si Incorporated (QSI) stock price today?

Quantum-Si Incorporated (QSI) is currently trading at $ 0.96, up 21.13% ($0.17) from the previous close of $ 0.80. Intraday prices update in real time during regular trading hours.

2.Is QSI stock going up or down today?

As of 2026-09-29 21:07:00, QSI is trading at $ 0.96, up 21.13% ($0.17) from its previous close of $ 0.80. The stock has traded between $ 0.61 and $ 14.17 during today’s regular session. Past price movements do not guarantee future results.

3.What is QSI pre-market price?

As of 2026-09-29 21:07:00, QSI is trading at $ 0.81 in pre-market trading, up 2.39% ($0.02) from the previous close of $ 0.80. Pre-market prices reflect trading activity before the regular session opens and may experience lower liquidity and higher volatility.

4.What is QSI after-hours price?

As of 2026-09-29 21:07:00, QSI is trading at $ 0.97 in after-hours trading, up 21.64% ($0.17) from the regular-session close of $ 0.80. After-hours prices may differ from the regular session’s opening price due to lower liquidity and wider bid-ask spreads.

5.Is QSI stock trading now?

QSI trades on the NASDAQ exchange during regular hours, Monday through Friday, 9:30 AM to 4:00 PM ET, excluding public holidays. Pre-market and after-hours trading are also available through select brokers outside these hours.

6.Where does QSI sit relative to its 52-week high and low?

Over the past 52 weeks, QSI has traded between a low of $ 0.69 and a high of $ 3.10. At $ 0.96, the stock is positioned 11.3% of the way from its 52-week low to its 52-week high, providing context for its current price within the one-year trading range.

7.What sector is Quantum-Si Incorporated in?

Quantum-Si Incorporated (QSI) operates in the MEASURING & CONTROLLING DEVICES, NEC sector. Sector classification helps investors compare it with companies exposed to similar market trends and competitive conditions.

8.What is Quantum-Si Incorporated's market capitalization and where is it listed?

Quantum-Si Incorporated is listed on the NASDAQ exchange with a market capitalization of $ 174.01M. Market cap reflects the total market value of all outstanding shares and is commonly used to classify stocks by size.

9.How is QSI valued in terms of P/E ratio and EPS?

QSI trades at a P/E ratio of --, based on trailing-twelve-month EPS of $ -0.45. P/E ratio compares the stock price to earnings per share and is a common starting point for assessing valuation relative to peers.

10.Does Quantum-Si Incorporated pay a dividend?

Quantum-Si Incorporated pays an indicated annual cash dividend of $ 0.00 per share, with a current dividend yield of 0.00% based on the latest share price. Dividend policies are subject to change at the board's discretion.