Product Comparisons

STM32F103 vs STM32F407: Which MCU is Right for You?

FPGACenter Team·April 11, 2026·4 min read·466 views

The STM32F103 and STM32F407 are two of the most popular microcontrollers in the embedded world. While both are part of ST's STM32 family, they target different performance tiers. This guide breaks down every key difference to help you make the right choice.

Quick Comparison Table

Feature	STM32F103	STM32F407
Core	ARM Cortex-M3	ARM Cortex-M4F
Max Clock	72 MHz	168 MHz
Flash	64KB – 512KB	512KB – 1MB
SRAM	20KB – 64KB	128KB – 192KB
FPU	No	Yes (single precision)
DSP	No	Yes
USB	Full-Speed (12 Mbps)	High-Speed OTG (480 Mbps)
Ethernet	No	Yes (MAC)
Camera	No	DCMI interface
Price Range	$1.50 – $4.00	$6.00 – $12.00

Architecture Deep Dive

Cortex-M3 vs Cortex-M4F

The fundamental difference is the processor core:

Cortex-M3 (STM32F103):

3-stage pipeline, Thumb-2 instruction set

Hardware multiply (single cycle 32×32)

No floating-point unit — all FP operations in software

Excellent for control-oriented tasks

Cortex-M4F (STM32F407):

3-stage pipeline with branch speculation

DSP instructions (SIMD, saturating arithmetic)

Single-precision FPU (IEEE 754 compliant)

2.5× faster for DSP/math-heavy workloads

Performance Benchmarks

Real-world benchmark comparison:

Benchmark	F103 (72 MHz)	F407 (168 MHz)	Speedup
CoreMark	91	565	6.2×
Dhrystone (DMIPS)	89	210	2.4×
FFT 1024-pt (float)	~45 ms	~2.1 ms	21×
GPIO toggle rate	18 MHz	84 MHz	4.7×

The FPU makes an enormous difference for any floating-point math — up to 21× faster for FFT operations.

Peripheral Comparison

Communication Interfaces

STM32F103:

3× USART

2× SPI

2× I2C

1× USB Full-Speed

1× CAN

STM32F407:

6× USART (4× UART)

3× SPI (+ I2S)

3× I2C

1× USB OTG HS + 1× USB OTG FS

2× CAN

Ethernet MAC

DCMI (camera interface)

SDIO

ADC Performance

Both have 12-bit ADCs, but with different capabilities:

F103: 2× ADC, 1 MSPS, 16 channels

F407: 3× ADC, 2.4 MSPS, 24 channels, triple interleaved mode (7.2 MSPS effective)

Timer Resources

Both are well-equipped for motor control and PWM, but the F407 has more timers with more advanced features including synchronized multi-axis motor control.

When to Choose STM32F103

The F103 remains an excellent choice for:

Simple control applications — sensor reading, relay control, LED driving

Cost-sensitive products — $1.50 unit cost at volume

Low-power designs — lower active current at lower clock speeds

Legacy compatibility — vast ecosystem of existing libraries and designs

Beginner learning — extensive community tutorials available

When to Choose STM32F407

Choose the F407 when you need:

Floating-point math — PID controllers, sensor fusion, DSP

Audio processing — I2S interface + DMA + FPU

USB High-Speed — mass storage, high-bandwidth devices

Ethernet connectivity — IoT gateways, industrial networking

Camera/imaging — DCMI interface for OV7670 or similar

Complex applications — RTOS with many tasks, large codebases

Cost Analysis

At FPGACenter, current pricing:

STM32F103C8T6 (64KB Flash, LQFP-48): ~$2.85

STM32F407VGT6 (1MB Flash, LQFP-100): ~$8.50

For production volumes of 1000+, expect:

F103: $1.20 – $1.80

F407: $5.50 – $7.50

Conclusion

Choose STM32F103 if your application is simple, cost-sensitive, and doesn't need floating-point math or high-speed connectivity.

Choose STM32F407 if you need DSP capabilities, FPU, Ethernet, USB High-Speed, or more resources for complex applications.

Both are excellent microcontrollers backed by ST's comprehensive HAL library and STM32CubeIDE toolchain. The right choice depends entirely on your specific requirements.

STM32MCUmicrocontrollerARMCortex-M3Cortex-M4comparison