COMPARISON · MULTIMETERS
Fluke 175 vs Fluke 177: Which Multimeter Should You Choose?
Choose the Fluke 177 if you work in dim panels, attics or under dashboards, or if you want the tighter DC volts spec: Fluke lists ±(0.09% + 2) on the 177 against ±(0.15% + 2) on the 175, and the 177 has a backlit display. Everywhere else Fluke's spec tables match line for line: True RMS AC volts and amps, 1000 V, 10 A, 50 MΩ, 10,000 µF, 100 kHz, CAT IV 600V / CAT III 1000V, the same 420 g case and a lifetime warranty. If you work in good light and your DC readings don't need better than about a sixth of a percent, the 175 does the same job.
By the OhmSavvy Research Team ·
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Fluke 177
4.6★★★★★The middle 170-series meter: 0.09% DC volts, True RMS to 10 A and a backlight, without paying for the 179's thermometer.
Fluke 175
4.5★★★★★The entry 170-series Fluke: True RMS volts and amps to 10 A, CAT IV 600V and a lifetime warranty, minus the 177's backlight.
Specs side by side
| Fluke 177 | Fluke 175 | |
|---|---|---|
| Rating | 4.6★★★★★ | 4.5★★★★★ |
| Accuracy | True RMS, ±(0.09% + 2) DC V | True RMS, ±(0.15% + 2) DC V |
| Safety rating | CAT III 1000V / CAT IV 600V | CAT III 1000V / CAT IV 600V |
| Auto-ranging | Yes (manual override) | Yes (manual override) |
| Best for | Everyday electrical troubleshooting | General electrical and electronic repair |
| DC volts accuracy | ±(0.09% + 2) to 60 V; ±(0.1% + 2) on 600 V and 1000 V | ±(0.15% + 2) on every range to 1000 V |
| AC volts (True RMS) | ±(1.0% + 3), to 1000 V | ±(1.0% + 3), to 1000 V |
| Display | 6,000 counts, 33-segment bar graph, backlight | 6,000 counts, 33-segment bar graph, no backlight |
| DC / AC current | ±(1.0% + 3) / ±(1.5% + 3), 0.01 mA to 10 A | ±(1.0% + 3) / ±(1.5% + 3), 0.01 mA to 10 A |
| Resistance | ±(0.9% + 1), to 50 MΩ | ±(0.9% + 1), to 50 MΩ |
| Capacitance | ±(1.2% + 2), 1 nF to 10,000 µF | ±(1.2% + 2), 1 nF to 10,000 µF |
| Frequency | ±(0.1% + 1), to 100 kHz | ±(0.1% + 1), to 100 kHz |
| Temperature | No (Fluke 179 only) | No (Fluke 179 only) |
| Battery | 9 V, about 200 h without backlight | 9 V, about 200 h without backlight |
| Size / weight | 43 × 90 × 185 mm, 420 g | 43 × 90 × 185 mm, 420 g |
| Warranty | Lifetime | Lifetime |
Specs checked against manufacturer documentation and official Amazon listings. Desk research, not bench testing. How we research.
Key differences
- →The 177 has a backlit display and the 175 doesn't: Fluke's 170 Series datasheet lists the backlight for the 177 and 179 only, and the 175's Amazon photo shows no backlight key.
- →DC volts accuracy: ±(0.09% + 2) on the 177's ranges up to 60 V and ±(0.1% + 2) on its 600 V and 1000 V ranges, against ±(0.15% + 2) on every 175 range.
- →Same display: the datasheet says all other specs match, so the 175 also has 6,000 counts and a 33-segment bar graph.
- →Every other line in Fluke's two spec tables is identical: AC volts, both current functions, resistance, capacitance, frequency, safety ratings, size, weight, battery and warranty.
- →Neither has temperature, LoZ, non-contact voltage or a low-pass filter. Temperature starts at the Fluke 179.
Fluke 175 vs 177 at a glance
Shared core
True RMS, 1000 V, 10 A, 50 MΩ, 10,000 µF and 100 kHz, with identical accuracy apart from DC volts.
177 extra: backlight
A lit display for dark work spots. Fluke lists none on the 175.
177 extra: 0.09% DC
Tighter basic DC volts accuracy than the 175's 0.15%.
Same protection
CAT IV 600V and CAT III 1000V on both, with UL, CSA and TÜV listings.
Same body
43 × 90 × 185 mm, 420 g, one 9 V cell and a lifetime warranty.
Verdict
Pay for the 177 if you work in poor light. Otherwise the 175 measures the same things.
Neither meter has been hands-on tested by OhmSavvy, so our scores (4.6 for the 177, 4.5 for the 175) come from Fluke's published specs. Every number on this page comes from Fluke's 175 and 177 product pages or the official Amazon listings. Where Fluke publishes nothing, we say "not stated" and don't guess.
Fluke 175 vs Fluke 177 spec by spec
Fluke uses the same accuracy table layout for every 170-series meter, listing the best accuracy for each function. Put the 175 and 177 tables side by side and they differ in one measurement row and one feature.
| Function | Fluke 175 | Fluke 177 | Match? |
|---|---|---|---|
| DC volts | ±(0.15% + 2), 0.1 mV res, 1000 V | ±(0.09% + 2) to 60 V, ±(0.1% + 2) above; 1000 V | 177 tighter |
| AC volts, True RMS | ±(1.0% + 3), 1000 V | ±(1.0% + 3), 1000 V | Same |
| DC current | ±(1.0% + 3), 0.01 mA res, 10 A | ±(1.0% + 3), 0.01 mA res, 10 A | Same |
| AC current, True RMS | ±(1.5% + 3), 10 A | ±(1.5% + 3), 10 A | Same |
| Resistance | ±(0.9% + 1), 0.1 Ω to 50 MΩ | ±(0.9% + 1), 0.1 Ω to 50 MΩ | Same |
| Capacitance | ±(1.2% + 2), 1 nF to 10,000 µF | ±(1.2% + 2), 1 nF to 10,000 µF | Same |
| Frequency | ±(0.1% + 1), 0.01 Hz to 100 kHz | ±(0.1% + 1), 0.01 Hz to 100 kHz | Same |
| Continuity, diode | Yes | Yes | Same |
| Hold, Auto Hold, Min/Max-average | Yes | Yes | Same |
| Display | 6,000 counts, 33-segment bar graph | 6,000 counts, 33-segment bar graph | Same |
| Backlight | No (datasheet: 177 and 179 only) | Yes | 177 only |
| Safety | CAT III 1000V / CAT IV 600V | CAT III 1000V / CAT IV 600V | Same |
| Battery life | 9 V, about 200 h (page says without backlight) | 9 V, about 200 h without backlight | Same |
| Operating temperature | −10 °C to +50 °C | −10 °C to +50 °C | Same |
| Warranty | Lifetime | Lifetime | Same |
What 0.09% vs 0.15% means on a real reading
An accuracy spec such as ±(0.15% + 2) has two parts. The first is a share of whatever the display shows. The second is a fixed number of counts, meaning steps of the last digit on the range in use. Both meters use "+ 2", so the gap between them is the percentage term, and that term grows with the reading.
Worked through for common DC jobs, the percentage term alone gives these figures:
| DC reading | 175 (0.15%) | 177 (0.09%) | Gap |
|---|---|---|---|
| 1.5 V AA cell | ±2.3 mV | ±1.4 mV | 0.9 mV |
| 12.6 V lead-acid battery | ±18.9 mV | ±11.3 mV | 7.6 mV |
| 24 V control supply | ±36 mV | ±21.6 mV | 14.4 mV |
| 48 V battery bank | ±72 mV | ±43.2 mV | 28.8 mV |
| 400 V DC string (600 V range) | ±0.60 V | ±0.40 V (0.1% on this range) | 0.20 V |
Fluke's 170 Series datasheet confirms both meters use the same 6,000-count display, which lets us finish the arithmetic. 12.6 V lands on the 60.00 V range, which steps in 0.01 V, so the two counts add 0.02 V on either meter: about ±0.039 V in total on the 175 and ±0.031 V on the 177. Either way, the spread on a car battery is tens of millivolts. The difference between a charged and a half-discharged lead-acid battery is a few hundred millivolts, so either meter makes that call easily.
The tighter spec starts to matter when you are checking something with its own tight tolerance. A common rule of thumb is that the meter should be several times more accurate than the thing being judged. Checking a 0.5% regulator output or a sensor excitation voltage against a datasheet limit leaves more margin at 0.09% than at 0.15%. For a broader explanation, read our guide to multimeter accuracy for electronics repair.
Fluke 177 vs 175: features and measurement differences, range by range
Fluke's product pages give one best-case figure per function. Its 170 Series detailed specifications go range by range, and they show one detail the product pages hide: the 177's 0.09% DC spec covers its ranges up to 60 V, and its 600 V and 1000 V ranges are specified at ±(0.1% + 2). The 175 holds ±(0.15% + 2) on every DC range. The datasheet also states that apart from the backlight, the DC volts line and the 179's temperature input, every other specification is the same for all three models.
| Function and range | Resolution | Fluke 175 | Fluke 177 |
|---|---|---|---|
| DC mV, 600.0 mV | 0.1 mV | ±(0.15% + 2) | ±(0.09% + 2) |
| DC V, 6.000 V and 60.00 V | 0.001 / 0.01 V | ±(0.15% + 2) | ±(0.09% + 2) |
| DC V, 600.0 V and 1000 V | 0.1 / 1 V | ±(0.15% + 2) | ±(0.1% + 2) |
| AC V, 600.0 mV to 1000 V, 45 to 500 Hz | 0.1 mV to 1 V | ±(1.0% + 3) | ±(1.0% + 3) |
| AC V, 500 Hz to 1 kHz | Same | ±(2.0% + 3) | ±(2.0% + 3) |
| DC A, 60.00 mA / 400.0 mA | 0.01 / 0.1 mA | ±(1.0% + 3) | ±(1.0% + 3) |
| DC A, 6.000 A / 10.00 A | 0.001 / 0.01 A | ±(1.0% + 3) | ±(1.0% + 3) |
| AC A, 60 mA to 10 A, 45 Hz to 1 kHz | 0.01 mA to 0.01 A | ±(1.5% + 3) | ±(1.5% + 3) |
| Ohms, 600.0 Ω | 0.1 Ω | ±(0.9% + 2) | ±(0.9% + 2) |
| Ohms, 6.000 kΩ to 6.000 MΩ | 1 Ω to 1 kΩ | ±(0.9% + 1) | ±(0.9% + 1) |
| Ohms, 50.00 MΩ | 10 kΩ | ±(1.5% + 3) | ±(1.5% + 3) |
| Capacitance, 1000 nF to 100.0 µF | 1 nF to 0.1 µF | ±(1.2% + 2) | ±(1.2% + 2) |
| Capacitance, 9999 µF range | 1 µF | 1.2% to 1000 µF; 10% typical above | 1.2% to 1000 µF; 10% typical above |
| Frequency, 99.99 Hz to 99.99 kHz | 0.01 Hz to 0.01 kHz | ±(0.1% + 1) | ±(0.1% + 1) |
| Diode test, 2.400 V | 0.001 V | ±(1% + 2) | ±(1% + 2) |
| Continuity | — | Beeps below 25 Ω; catches 250 µs opens/shorts | Same |
A few measurement details apply to both meters and are worth knowing before you buy either. Min/Max/Avg is specified at ±12 counts for DC changes lasting longer than 275 ms and ±40 counts for AC changes longer than 1.2 s, so it suits sags and slow drifts rather than spikes. The continuity beeper catches opens or shorts as brief as 250 µs, which makes a wiggle test on a cord or harness useful. Above 1,000 µF the capacitance reading is a 10% typical figure, which is fine for a sanity check on a big filter capacitor but too loose to grade one against its tolerance. In the mA and A ranges, frequency is specified only to 30 kHz.
Two source conflicts to note. Fluke's product pages give the frequency ceiling as 100 kHz and the range table runs to 99.99 kHz, while the datasheet's nominal summary says 2 Hz to 50 kHz; we follow the range table. The product pages list capacitance to 10,000 µF, the datasheet's top range is 9,999 µF. Neither conflict separates the 175 from the 177, because both models share those lines.
Do you need the backlight?
The backlight is the difference you notice most in daily use. Fluke describes the 177's display as having a backlight for poorly lit areas. The 175's page doesn't mention one, Fluke's 170 Series datasheet lists the backlight for the 177 and 179 only, and the 175's Amazon photo shows no backlight key on the front panel. Think about where you will be holding the meter:
| Where you read the meter | Light | Better fit |
|---|---|---|
| Bench or workshop | Good, overhead | Either |
| Residential panel in a garage or basement | Often poor | 177 |
| Attic air handler or crawlspace | Dark | 177 |
| Under a dashboard or in a footwell | Dark | 177 |
| Outdoor equipment in daylight | Bright | Either |
| Control cabinet on a plant floor | Mixed, shadowed | 177 |
Battery life is the trade-off. Fluke quotes about 200 hours from an alkaline 9 V for both meters, and both pages qualify the figure as "without backlight", the same wording even on the 175. Fluke doesn't say how much the light shortens it, but any display light draws extra current, so a 177 owner who leaves it on will change batteries more often than a 175 owner. A headlamp gets a 175 owner through the same jobs, at the cost of a free hand.
What both meters share, and what neither does
Most of what you pay for in a 170-series Fluke is common to both. AC readings are True RMS, so the readings from LED drivers, switch-mode supplies and drive inputs stay within the published spec instead of drifting the way an average-responding meter's do. Both accept 1000 V AC or DC, carry CAT IV 600V for service-entrance work, resolve current to 0.01 mA on the low range and take 10 A on a separate jack. Capacitance runs to 10,000 µF, enough for large motor-start and power-supply capacitors, and frequency runs to 100 kHz.
The gaps are shared too. Fluke lists no temperature function on either; that is what the Fluke 179 adds over the 177. Neither has a low-impedance (LoZ) input for ghost voltage or a non-contact sensor; for those, compare the Fluke 177 with the 117. Neither lists a low-pass filter for the motor side of a variable-frequency drive, so for that work see Fluke 87V vs 179.
Same case, same warranty, one real upgrade
Fluke 175 or 177: which should you buy?
| You are… | Better fit | Why |
|---|---|---|
| Residential or commercial electrician | Fluke 177 | Panels and ceilings are often dim; same CAT IV rating either way |
| HVAC technician | Fluke 177, or 179 | Attic and crawlspace work favors the backlight; the 179 adds temperature |
| Electronics hobbyist at a bench | Fluke 175 | Good light, and 0.15% DC is ample for most circuits |
| Calibration-minded technician | Fluke 177 | 0.09% DC leaves more margin against tight tolerances |
| Automotive DIYer | Fluke 177 | Footwells and engine bays are dark; 12 V readings are fine on either |
| Solar or battery-bank installer | Fluke 177 | 1000 V DC on both; the tighter DC spec helps on string and cell checks |
| Budget-first buyer wanting a lifetime warranty | Fluke 175 | Same protection, body and warranty for less |
For the wider field, including the meters these two compete with, see our best multimeters roundup and the best multimeter for electricians guide.
Safety: the rating only counts if the leads match it
Choose the Fluke 177 if…
- ✓You read meters in dark panels, crawlspaces, attics or footwells, where a backlit display saves holding a flashlight
- ✓You check DC sources against a tight tolerance and want the 0.09% basic DC accuracy
- ✓You want the 170 Series backlight without paying for the 179's thermometer
Choose the Fluke 175 if…
- ✓You mostly work in daylight or a well-lit shop and won't miss a backlight
- ✓Your DC work is batteries, supplies and control voltages, where 0.15% is already far finer than the job needs
- ✓You want the CAT IV 600V rating and lifetime warranty of the 170 series at the lowest entry point
The bottom line
The Fluke 177 is the better meter, but only by two things: a backlit display and DC volts accuracy of ±(0.09% + 2) against the 175's ±(0.15% + 2). If you work in poor light or check DC against tight limits, buy the 177. If you work in good light and your DC readings are batteries, supplies and controls, the 175 gives you the same True RMS ranges, CAT IV 600V rating, 420 g body and lifetime warranty.
Frequently asked questions
What is the difference between the Fluke 175 and 177?+
Two things, per Fluke's spec pages. The 177 has a backlit display, and its DC volts accuracy is ±(0.09% + 2) against the 175's ±(0.15% + 2). Every other published line matches, including True RMS AC, 10 A current, 50 MΩ, 10,000 µF, 100 kHz, the CAT IV 600V rating, the 420 g body and the lifetime warranty.
Is the Fluke 177 more accurate than the 175 on every range?+
Only on DC volts, and not by the same margin on every range. Fluke's 170 Series datasheet gives the 177 ±(0.09% + 2) from 600 mV to 60 V and ±(0.1% + 2) on the 600 V and 1000 V ranges, against ±(0.15% + 2) throughout on the 175. AC volts, current, resistance, capacitance, frequency and diode test carry identical specs on both.
Does the Fluke 175 have a backlight?+
No. Fluke's 170 Series detailed specifications list the backlight as a 177 and 179 feature only, the 175 product page never describes a lit display, and the main photo on the official Amazon listing shows no backlight key, while the 177's photo does. If you often read the meter in a dark panel or crawlspace, the 177 is the safer choice.
How many counts is the Fluke 175 display?+
6,000 counts, the same as the 177. The 175 product page doesn't say, but Fluke's 170 Series detailed specifications give 6,000 counts at four updates a second and a 33-segment bar graph at 40 updates a second, and state that every spec other than the backlight, DC volts accuracy and temperature is shared by the 175, 177 and 179.
Is the Fluke 177 worth the upgrade from the 175?+
It is if you work in dim places or need tighter DC readings. The backlight saves holding a flashlight in panels, attics and footwells, and 0.09% DC accuracy leaves more margin when checking regulated supplies. If your work is in good light and you read batteries and control voltages, the 175 measures the same things with the same safety rating.
Can the Fluke 175 or 177 measure temperature?+
No. Fluke lists temperature only on the Fluke 179 in this series, with a −40 °C to 400 °C range and an 80BK probe in the box. The 175 and 177 have no thermocouple input. If you do HVAC work, compare the 177 and 179, which otherwise share the same accuracy table.
Are the Fluke 175 and 177 safe for electrical panels?+
Yes, within their ratings. Both carry CAT III 1000V and CAT IV 600V, which covers distribution panels and the service entrance on systems up to 600 V to ground. Use leads with a matching rating, check the meter on a known live source before and after testing, and leave service-entrance work to qualified electricians.
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