Today we're taking a look at the all-new FireBoard Spark, the only instant-read thermometer with an external probe port that allows it to also function as a leave-in thermometer.

We recently published our roundup of the Best Instant-Read Thermometers and the FireBoard Spark tied with the Thermoworks Thermapen One and proved to be the best high-tech choice out of the lot.

Grilling Gift Guide

Looking for gift ideas for yourself or someone special in your life? We've got you covered.

the cloud connected Fireboard Spark with a leave in probe port could be your next FireBoard device

Note: Some of the links in this article may be affiliate links. This doesn’t cost you any more than normal but it helps support our channel. Read our disclaimer for more info.

Why Trust Our Review?

We actually use this product and all the other products that we review. You can tell because we're using our own pictures and capturing our own video rather than using stock images from the manufacturers. That means we have first-hand knowledge about the FireBoard Spark and aren't just regurgitating the information found on manufacturers' websites.

Do we make money if you make a purchase with our link? Yes. That's how we get paid for the work that we do. But we will not waste our time and compromise our reputation by recommending a product that we've had a bad experience with.

FireBoard Spark Instant-Read Thermometer: But Better

While the FireBoard Spark is an instant-read thermometer, it is so much more than just that.

The FireBoard Spark features include an instant read probe that folds out to 180°

Features and Specifications

  • Temperature Range: -58 to 572 ̊F (-50 to 300 ̊C)
  • Temperature Accuracy: ±0.7 ̊F (±0.4 ̊C) from -4 to 392 ̊F (-20 to 200 ̊C); ±1.8 ̊F (±1.0 ̊C) full range
  • Sensor Speed: 1 second
  • Resolution: 1.0° or 0.1° user selectable
  • Battery: 2600mAh Li-Ion rechargeable battery
  • Connectivity: WiFi, Bluetooth, and FireBoard Cloud-enabled
  • Waterproof: IP66
  • Rotating Screen: 4 ways
  • Calibration: Nist traceable calibration certificate
  • Probe Type: instant read thermocouple probe, external probe port for FireBoard thermister probes (sold separately)
  • Other Features: Built-in magnets, Sync mode

What We Loved About the FireBoard Spark


The FireBoard Spark gives highly accurate instant readings. We performed 3 different temperature reading tests in our recent head-to-head: boiling water, ice water, and medium rare 130° in a sous-vide.

Fireboard Spark instant read meat thermometer performing an ice bath test
Fireboard Spark instant read meat thermometer performing a boiling water test
Fireboard Spark instant read meat thermometer performing the medium rare test in a su-vide

In those tests, we measured the length of time it took each thermometer to reach its claimed accuracy point, which is ±0.7 ̊F for the FireBoard Spark.

Additionally, because it comes with a NIST traceable calibration certificate I know that it has been fully and accurately calibrated by FireBoard labs before even being shipped.

The FireBoard Spark proved to be an incredibly fast instant read thermometer taking the lead in the ice bath, and coming in second (by milliseconds) for the boiling and medium rare tests.


There were several features that caused the FireBoard Spark thermometer to rank high in usability. We loved the 4-way rotating screen and the fact that it has a sleep/awake mode. The display screen settings menu is quite robust for an instant-read thermometer and makes tasks like changing the resolution to 1.0° or 0.1° or temperature readings from °F to °C a breeze.

The display screen settings on the Fireboard Spark


The FireBoard Spark was the only instant-read thermometer with built-in magnets that we could really trust. Only about half of the thermometers we tested even had magnets, but the others were all quite weak and did not hold onto metal surfaces very strongly. The magnets on the FireBoard Spark are solid, giving this instant-read thermometer many more options for easy storage.

the Fireboard Spark had the strongest magnet


The FireBoard Spark was the only instant-read thermometer we tested that was rechargeable. It includes a USB c rechargeable li-ion battery and comes with a USB c charging cable. With normal use, FireBoard claims the battery will last up to 12 or more months and we have found that to be pretty accurate.

The Fireboard Spark has a USB c charging cable plugged into the charging port


FireBoard Spark offers a number of features simply not found in any of the other competitors. And to be honest, it took us a little while to really figure out when we had actually reached the limits of what it was capable of. However, in keeping with being honest, the Spark is only capable of functioning to its fullest if you also have other FireBoard devices and products in your collection.

In addition to the instant-read probe, the Spark has a leave-in probe port that can accept any external FireBoard probe. This allows the Spark to function as a single-channel FireBoard to monitor temperature readings throughout an entire cook, rather than just single instant readings.

This is an awesome feature and a significant upgrade from your standard instant-read thermometer, however, external probes are sold separately and do not come with the purchase of a FireBoard Spark. (See "What Can Be Improved" below).

The FireBoard Spark also has something called Sync Mode which is only of interest if you also have a FireBoard. When you turn Sync Mode on, your Spark becomes a remote FireBoard monitor that you can stick to the fridge or set on the counter. This uses the FireBoard Cloud to allow you to visually keep track of all your FireBoard temperatures through the remote display screen rather than having to pull the app up on your mobile device.

Ultimately, the FireBoard Spark is not just an instant-read thermometer. And that's why the incredibly versatile instant-read FireBoard Spark costs more than other instant-read thermometers on the market.

Haptic Feedback

The FireBoard Spark was also the only thermometer we tested to offer haptic feedback. This basically means that your hand will feel a slight buzz when the Spark instant-read thermometer has captured a final temperature reading. It might seem insignificant, but it's actually kind of nice and helpful.

What Could Be Improved


The FireBoard Spark only offers a one-year warranty which is the shortest of all the instant-read thermometers we reviewed. The longest warranty was for the Thermapen One, at five years. Considering that Thermapen is what I would consider FireBoard Spark's greatest competitor, that seems like a pretty significant difference when the Spark is considerably more expensive.

Including External Probe with Purchase

I already mentioned it briefly above, but the main reason this instant-read is worth the higher price tag is because of the leave-in probe port and its ability to do long-term temperature tracking. However, you have to purchase the external probe separately.

FireBoard Spark using external food probe to track temperature in a long cook

A basic food probe is only $15, but when you consider the Spark is only worth the price if you add that additional purchase, then really you're spending $164 rather than $149.

I personally hope to see FireBoard include a free external probe with the purchase of the Spark in the future.

Digital Readout

The FireBoard Spark instant-read thermometer has an awesome display and a fast response time. However, oddly enough, sometimes that can actually make it difficult to read. I notice it especially when I have it set to include the decimal point. When the tenths of a degree are constantly fluctuating, the numbers just kind of melt together in the display, and my eyes and brain can't process what I'm actually seeing.

Fireboard Spark digital meat thermometer

In some of our testing when we were comparing the results of 5 different thermometers, results often came down to the tenths of a second. Other instant-read displays seemed to handle that better. However, when not testing this unit against others, we keep it set to exclude the decimal and it is MUCH easier to read.

Our Fireboard Spark Review

Our FireBoard Spark Review: Final Thoughts

If you own other FireBoard devices and are in the market for an instant-read food thermometer, it makes absolute sense for you to choose the FireBoard Spark. You definitely won't be disappointed.

The external probe port is a powerful feature that sets it above the Thermapen One. The fact that it's FireBoard cloud enabled and allows you to monitor all your FireBoard temperatures makes this a slam dunk addition to your FireBoard collection.