Raspberry Pi Temperature Guide: How to Check, Throttling Limits & Cooling Tips
Jan 14th,2025
Raspberry Pi temperature is a critical factor in real-world deployments, especially considering how small, silent, and capable the board is for its size.That same compact form factor, however, makes temperature management one of the most important factors in real-world deployments. Unlike a desktop PC or server with large heatsinks and multiple fans, a Raspberry Pi relies on minimal cooling by default. As workloads increase, heat builds up quickly, increasing the risk of Raspberry Pi overheating.
Temperature directly affects performance, stability, and long-term reliability, which can be better understood through the Raspberry Pi basics covered in SunFounder’s Raspberry Pi Getting Started course，especially under sustained workloads.When a Raspberry Pi gets too hot, it automatically reduces CPU speed to protect itself. This process, called thermal throttling, prevents immediate damage but comes at the cost of slower execution and unpredictable performance. In long-running or unattended setups, ignoring temperature can lead to system slowdowns, service interruptions, or reduced hardware lifespan due to poor Raspberry Pi temperature control.
Common Use Cases Where Temperature Is Critical
Temperature becomes especially important when a Raspberry Pi is used continuously or under sustained load, as explained in our Raspberry Pi System Monitor Guide on SunFounder.Common scenarios include:
Servers and NAS systems
Running services such as web servers, file servers, or databases keeps the CPU active for long periods, raising Raspberry Pi CPU temperature under continuous load.Disk I/O, encryption, and network traffic all contribute to heat buildup.
IoT gateways and edge devices
In IoT deployments, Raspberry Pi boards often run 24/7, handling MQTT brokers, data processing, or protocol translation. These systems are frequently enclosed and deployed in warm environments, making Raspberry Pi temperature monitoring especially important.
Kiosks and digital signage
Displays driven continuously at high resolutions generate GPU load and internal heat. Poor airflow behind screens or inside enclosures can easily lead to Raspberry Pi overheating
Long-running workloads
Docker containers, compilers, video processing, or AI inference tasks can easily sustain high CPU usage for hours. Without cooling, temperature limits are reached quickly.
In all of these cases, temperature is not a theoretical concern—it directly impacts system behavior.
Understanding Raspberry Pi Thermal Limits
• Official Operating Temperature Ranges
• Raspberry Pi boards are generally designed to operate in ambient temperatures up to around 50 °C. This refers to the surrounding environment, not the CPU itself. The SoC is designed to tolerate much higher internal temperatures, but only for short periods beyond the Raspberry Pi temperature limit.
• Recommended vs Maximum Temperatures
For day-to-day use, maintaining a safe Raspberry Pi temperature below 60–65 °C is ideal.Temperatures between 65–75 °C are acceptable under load but should not be constant. Once the CPU approaches 80 °C, the system begins to protect itself.
The absolute maximum is higher, but reaching it frequently is a sign that cooling is insufficient.
| Temperature Range | Status | Description |
|---|---|---|
| Below 60 °C | Ideal | Optimal for long-term reliability |
| 60–70 °C | Normal | Typical under moderate load |
| 70–80 °C | Warm | Acceptable short-term, monitor closely |
| Above 80 °C | Throttling | Performance reduction begins |
| Near 85 °C | Critical | Aggressive protection engaged |
Throttling Thresholds: Soft vs Hard Limits
• Soft throttling typically starts around 80 °C. The CPU frequency is gradually reduced.
• Hard throttling or emergency limits occur closer to 85 °C, where more aggressive measures are taken to prevent damage, a behavior that can be observed in real-world system control projects such as SunFounder’s Radar Guard 3.0.
These thresholds are automatic and cannot be ignored by software.
https://www.raspberrypi.com/news/heating-and-cooling-raspberry-pi-5/
What Happens When the Pi Overheats
When overheating occurs:
• CPU frequency is reduced
• Performance becomes inconsistent
• Time-sensitive tasks slow down
• Latency increases
• In extreme cases, the system may become unresponsive
Over time, constant thermal stress can degrade components.
Differences Between Models
Raspberry Pi 3
Lower power consumption and lower peak performance. It can still throttle under load but is generally easier to cool passively
Raspberry Pi 4
More powerful CPU and higher thermal output. Under sustained load, throttling is common without a heatsink or fan, as explained in the official Raspberry Pi article on heating and cooling Raspberry Pi 5
Raspberry Pi 5
Significantly higher power draw and performance result in higher Raspberry Pi 5 temperature under sustained workloads.Active cooling is strongly recommended, even for moderate workloads. Thermal design is no longer optional.
How to Check Raspberry Pi Temperature
Command-Line Method
To check Raspberry Pi temperature, the simplest and most common method is:
vcgencmd measure_temp
This returns the current CPU temperature in degrees Celsius.
Reading via the /sys Filesystem
Another reliable method is:
cat /sys/class/thermal/thermal_zone0/temp
This outputs a raw value in millidegrees. Divide by 1000 to get Celsius.
• Checking Throttling Status
To see if throttling has occurred, run:
vcgencmd get_throttled
This command reports current and past throttling events, including undervoltage and thermal issues.
Common status bits explained (simplified):
× Thermal throttling: The CPU has reduced its speed due to high temperature.
× Undervoltage detected: The power supply could not provide sufficient voltage, often caused by weak adapters or cables.
| Bit | Hex | Meaning |
|---|---|---|
| 0 | 0x1 | Undervoltage currently detected |
| 1 | 0x2 | ARM frequency currently capped |
| 2 | 0x4 | Currently throttled due to temperature |
| 3 | 0x8 | Soft temperature limit currently active |
Thermal Throttling Explained
Thermal throttling is a hardware-level safety mechanism. When the CPU exceeds safe temperature limits, clock speed and voltage are reduced automatically.
Impact on Performance
Lower CPU frequency means:
• Slower processing
• Longer response times
• Reduced throughput for servers and services
Because throttling happens dynamically, performance may fluctuate depending on temperature, as explained in the official Raspberry Pi article on heating and cooling Raspberry Pi 5.
Long-Term Impact
Frequent throttling does not immediately damage the board, but it:
• Reduces predictable performance
• Increases wear from thermal cycling
• Signals inadequate cooling design
Cooling Options for Raspberry Pi
Passive Cooling
Heatsinks
Aluminum or copper heatsinks, such as a Raspberry Pi heatsink, increase surface area and are often sufficient for light workloads.
Metal cases
Some cases act as large heatsinks themselves, transferring heat away from the SoC efficiently.
Active Cooling
Fans
A Raspberry Pi fan can dramatically reduce temperatures under load.and are inexpensive.
Fan HATs
Stackable boards with temperature-controlled fans provide automatic cooling.
Official Cooling Solutions
Official cases and active coolers are designed to match the board’s thermal characteristics and offer reliable performance.
Case Design and Airflow
Good airflow matters as much as the fan itself. Avoid sealed plastic cases for high-load scenarios unless active ventilation is included.
Temperature Monitoring & Alerts
Logging Temperature Over Time
Simple scripts can record temperature at regular intervals to a file, making trends easy to analyze, as described in the official Raspberry Pi guide on checking CPU temperature
Cron Jobs
Cron can be used to:
• Log temperature
• Trigger warnings
• Restart services if limits are exceeded
Integration with Monitoring Tools
Advanced setups often integrate Raspberry Pi temperature into:
• Prometheus for metrics collection
• Node-RED for logic and dashboards
• ThingsBoard for IoT-scale monitoring and alerts
This is especially useful in multi-device or industrial environments.
Raspberry Pi Temperature FAQ
What is a safe Raspberry Pi temperature for long-term operation?
Below 60 °C is ideal. Short spikes higher are normal under load.
Is running at 70–80 °C dangerous?
Occasional operation in this range is acceptable, but sustained use suggests insufficient cooling.
Does thermal throttling damage the hardware?
No. It protects the hardware, but frequent throttling reduces performance predictability.
Can long-term heat reduce lifespan?
Yes. Consistently high temperatures can shorten component lifespan over time.
Is passive cooling enough for 24/7 operation?
For light workloads, often yes. For servers, containers, or Raspberry Pi 5, passive cooling alone is usually insufficient.
Does adding a fan always improve performance?
In sustained workloads, yes. A fan prevents throttling, allowing the CPU to maintain higher clock speeds consistently.
