⭐ Customer Reviews and Testimonials

Authentic User Feedback

📚 Student User Reviews

⭐⭐⭐⭐⭐ Emily Tran - High School Student
"I bought this calculator for my AP Calculus class in October 2024, and it’s been a game-changer. The multi-line display makes it so much easier to check my work, and the 240 functions cover everything we’ve thrown at it—from derivatives to statistical distributions. The solar + battery power means I never worry about it dying during exams."

Purchase Date: October 2024 | Usage Period: 5 months

🔧 Engineering Professional Reviews

⭐⭐⭐⭐⭐ Raj Patel - Civil Engineer
"Been using the CTIFREE fx-991ES PLUS daily since January 2025 for field calculations and design checks. The trigonometric and exponential functions are spot-on, and the keys are responsive even with gloves on. The protective case is a nice touch—it’s survived a few drops on construction sites!"

Purchase Date: January 2025 | Usage Period: 6 months

🎓 University Student Reviews

⭐⭐⭐⭐☆ Amina Khalid - Physics Major
"Great calculator overall. I got it in August 2024 before my second year, and it’s handled all my physics and math coursework. The only reason I didn’t give 5 stars is that the manual is a bit confusing at first—there’s a learning curve with so many functions. But once you get used to the mode settings, it’s incredibly powerful."

Purchase Date: August 2024 | Usage Period: 7 months

👨‍🏫 Educator Reviews

⭐⭐⭐⭐⭐ David Wu - Math Teacher
"I recommend this model to all my senior students. Purchased mine in March 2025 to test alongside my curriculum, and it’s perfect for everything from algebra to statistics. The large LCD display is clear even in dimly lit classrooms, and the dual power system means no more dead batteries during lessons. It strikes the right balance between functionality and ease of use."

Purchase Date: March 2025 | Usage Period: 3 months

💼 Professional Use Review

⭐⭐⭐⭐⭐ Sofia Ramirez - Financial Analyst (using for technical modeling)
"Though I work in finance, I needed a reliable tool for quick engineering-style calculations during project evaluations. Bought the CTIFREE fx-991ES PLUS in December 2024. It’s not a financial calculator, but its statistical and exponential functions are excellent for forecasting models. Lightweight, durable, and the solar assist is surprisingly effective—even under office lighting."

Purchase Date: December 2024 | Usage Period: 6 months

📊 Rating Statistics

Average Rating: 4.8/5 ⭐ (203 Reviews)

Detailed Rating Distribution:

• ⭐⭐⭐⭐⭐ (5-star): 156 reviews (76.8%)
• ⭐⭐⭐⭐☆ (4-star): 37 reviews (18.2%)
• ⭐⭐⭐☆☆ (3-star): 7 reviews (3.4%)
• ⭐⭐☆☆☆ (2-star): 2 reviews (1.0%)
• ⭐☆☆☆☆ (1-star): 1 review (0.5%)

🏆 Industry Expert Recommendations

Mathematics Education Expert Recommendation

Dr. Linda Foster - STEM Education Specialist
"After evaluating over a dozen scientific calculators for classroom adoption, I consistently come back to the CTIFREE fx-991ES PLUS. Its 240-function capacity aligns perfectly with high school and early university curricula. The intuitive layout reduces cognitive load, allowing students to focus on concepts rather than button sequences. A top choice for math educators."

Engineering Tools Consultant Recommendation

Mark Jensen - Professional Tools Advisor
"For non-graphing needs, this is one of the most reliable scientific calculators on the market. The dual power system and CE/FCC/RoHS certifications ensure it meets professional standards. I recommend it to junior engineers who need precision without the complexity of programmable or graphing models."

💬 Latest User Reviews

Recent 30-Day Review Highlights:

⭐⭐⭐⭐⭐ "Exactly What I Needed" - Nathan Brooks (University Freshman)

Posted: 2 days ago

"Used it for my midterm exams—no issues at all. The solar panel works great by my dorm window. Easy to read and fast to navigate. Perfect for STEM majors."

⭐⭐⭐⭐⭐ "Worth Every Penny" - Priya Mehta (Engineering Student)

Posted: 1 week ago

"I was using an old basic calculator and made so many errors. This one has improved my accuracy dramatically. Love the protective case and sturdy build."

⭐⭐⭐⭐☆ "Solid Performer" - Thomas Reed (Vocational Instructor)

Posted: 3 weeks ago

"Bought five for my students’ workshop. All perform consistently. Only feedback: the buttons could be slightly more tactile, but overall very satisfied."

🎯 Reviews by Use Case Category

📚 Academic Use – Students & Educators (132 Reviews)

• Average Rating: 4.9/5
• Most Praised Features:
• Comprehensive functions (91% mentioned)
• Clear display (89% mentioned)
• Exam-compliant design (85% mentioned)
• Durability with protective case (78% mentioned)

🧰 Professional Use – Engineers & Technicians (71 Reviews)

• Average Rating: 4.7/5
• Most Praised Features:
• Accuracy in advanced calculations (93% mentioned)
• Dual power reliability (88% mentioned)
• Portability and build quality (82% mentioned)
• Ease of use in field conditions (76% mentioned)