Trimming is the part of yard work that drifts to the ends of the day. The mowing gets a weekend slot; the edges along the drive, the beds and the fence get done before work or after dinner, when the street is quiet and the windows next door may be open. Our guide to the quietest string trimmers ranks the whole category and sets out who declares what. This guide asks the narrower question for that one job: which battery trimmer should you buy if you edge a small lot close to the neighbors, and what can you change about how you run it?
That changes three things. The guaranteed sound power, the figure for what the whole machine sends next door, leads the ranking. The figures at your ear are kept in groups by the test standard each maker names. And the settings, heads, line and batteries that decide how long a quiet session lasts sit beside the noise.
Our picks are listed above, with full specifications for each.
The neighbor's number comes first
Every trimmer here carries two declared quantities. LpA is the sound pressure at the operator's ear. LWA is sound power, the total acoustic output of the machine, and under the EU's outdoor noise directive, 2000/14/EC, makers print a guaranteed ceiling for it. Our explainer on sound power vs sound pressure covers why the two cannot be ranked against each other, and our page on keeping a quiet yard explains how they map onto the two audiences, you and the people over the fence.
At the ends of the day the second audience matters more, so the picks are ordered by guaranteed sound power. Lowest first, each a ceiling under 2000/14/EC:
- STIHL FSA 50: 84 dB(A), from the international manual for the FSA 50.0
- Husqvarna 520iLX: 89 dB(A), US product page
- Worx WG163: 90 dB(A), from the European manual for the WG163E
- STIHL FSA 57 and FSA 30: 91 dB(A), manuals
- Husqvarna 110iL FLXi: 92 dB(A), US product page
- STIHL FSA 60 R, FSA 70 R and FSA 86 R, and Husqvarna 525iLST: 93 dB(A)
- EGO ST1511T: 95 dB(A), from the European manual for the ST1510E-T
- STIHL FSA 80 R and EGO ST1534: 96 dB(A), the EGO with its line head
STIHL's 2021 US manual for the FSA 60 R gave a guaranteed 96 dB(A); its 2025 international manual gives 93, which is the figure in the list.
The FSA 50 sits nine decibels under the cluster at 93, close to the 10 dB that the National Park Service describes as a doubling of perceived loudness. Between the FSA 57 at 91 and the 110iL FLXi at 92 the gap is a single decibel, too small to choose on. Keep in mind that a guaranteed figure is a ceiling, not an average, and each maker sets its own margin: STIHL's FSA 50 manual gives a measured 82 under its guaranteed 84, Worx declares a measured 86 under its guaranteed 90, and EGO a measured 90 under its guaranteed 95 for the ST1510E-T.
Your ears: grouped by test standard
The figure at your ear matters too, since you stand over the head for the whole session. We rank it only within the standard each maker names beside it.
Measured to IEC 62841-4-4, in STIHL's 2024 to 2026 manual printings:
- FSA 50: 69 dB(A)
- FSA 57: 74 dB(A)
- FSA 30: 76 dB(A)
- FSA 70 R: 76 dB(A) with its line heads, 79 with PolyCut blades
- FSA 80 R: 81 dB(A), 82 with PolyCut blades
Measured to EN 50636-2-91:
- FSA 86 R: 77 dB(A), 80 with PolyCut blades
- FSA 60 R: 77 dB(A), 80 with PolyCut blades, in the 2025 international manual; the 2021 US manual gave 81
Other bases, kept out of both lists:
- Husqvarna 110iL FLXi: 73.4 dB(A) on the US page, no standard named
- Worx WG163: 74 dB(A), KpA 3, in the WG163E manual with no standard beside it; the declaration of conformity lists EN 50636-2-91 among the standards the tool meets
- Husqvarna 520iLX: 77 dB(A) in the US manual, an equivalent level measured to EN 62841-4-4; the US page says 76
- EGO ST1511T: 78.1 dB(A), K 3, no standard named
- Husqvarna 525iLST: 80 dB(A) to IEC 62841-1, in its manual
- EGO ST1534: 81.7 dB(A) with line, K 2.5, no standard named
The groups matter more than they look. STIHL's FSA 57 manual has printed the same 74 and 89 dB(A) under two standards: its 2021 and 2022 printings name EN 50636-2-91, its 2024 printings IEC 62841-4-4. STIHL did not change the numbers when it changed the standard, but that tells you about one tool from one maker, not about how another maker's figures would compare, so the lists stay apart.
Most of these figures are missing from the US documents. STIHL's North American manuals for the FSA 30.0, FSA 50.0 and FSA 70.0 R print no sound values at all. STIHL's international English manuals for the same model names, filed under the same document base numbers, 0458-039, 0458-070 and 0458-063, print them in full, and those are what this guide quotes. The FSA 57's US manual prints its own, as did the FSA 60 R's 2021 US manual. Our STIHL decibels page gathers the figures for the rest of STIHL's range.
Husqvarna prints both figures on its US pages, and the 520iLX and 525iLST US manuals add the ear figure with a standard but no sound power. Our Husqvarna decibels page covers where its pages and manuals disagree across the range.
Worx prints nothing in the US, but its numbering does the mapping for us. The US manual covers the WG163 and its WG163.X kits, the European manual the WG163E and its WG163E.X kits, and both list 7600/min, a 12 inch (30 cm) cut and 0.065 inch (1.65 mm) line.
EGO is where the rule bites. We carry a European figure to a US model only where EGO's numbering shows they are the same tool. The STX4500 uses one number in both markets, the EU ST1530E matches the US ST1530 and ST1534 rear motor trimmers, and the EU ST1510E-T matches the US ST1510T inside the ST1511T kit, down to two speeds and 3.5 kg. Two declarations do not carry over. EGO's UK page lists the ST1510E, declared at 72.6 dB(A) and a guaranteed 93, with an aluminum, non-telescoping shaft, and its EU manual describes no split, while EGO US sells that number only as the split shaft ST1510S and ST1511S and the telescopic ST1510T. And the ST1610E-T manual, declaring 77 dB(A) and a guaranteed 92, describes LINE-IQ feeding, which EGO US sells on the ST1623T rather than the ST1611T that shares its number. Our EGO decibels page lists every EGO declaration with its own view of each match.
The Milwaukee, DEWALT, Toro and RYOBI trimmer pages we opened print no decibel figure, and Makita's US site would not load for us. The parent guide found the same silence for Greenworks and Makita, and found these brands' European trimmers declaring under different model numbers from their US ones, so we map none of them.
The low setting, in the makers' words
Several of these trimmers can run below full speed, and every maker that describes it says the same two things: it lowers the speed, and it stretches the battery. None publishes a decibel figure at that setting, and none says which setting its declared figures describe.
- Husqvarna 520iLX. The US page: "SavE™ mode maximises the run time by lowering the rpm and is ideal for tasks that do not require full power." The manual adds that it "gives the longest operation time from the battery".
- Husqvarna 525iLST. Three speed levels. The manual: "A lower level increases the time of operation for the product" and "Do not use a higher level than necessary for the operation."
- STIHL FSA 70 R. An ECO power level. The manual: "When you select the ECO power level, the speed is reduced. This can extend the battery runtime." STIHL USA lists "Variable speed control in two levels" for the FSA 80 R and a variable-speed trigger on the FSA 60 R and FSA 86 R.
- EGO. The ST1510E-T manual lists low and high speeds of 4800 and 6000 rpm, and the STX4500 manual says "The low speed mode provides better control of the machine and longer operating time per charge."
- RYOBI and Toro. A "Variable Speed Trigger & 2 Speed Switch" on the RY402110, and "two speed ranges" on the Toro 51830T.
The FSA 50, FSA 57, FSA 30, WG163 and 110iL FLXi list no speed setting. For the FSA 50 that matters less on paper, because its one speed already carries the lowest declarations here. Whether a low setting lowers the declared figures of the others, and by how much, no maker says.
Line or blade: the head changes the answer
STIHL declares by head, and the results run both ways. On the FSA 70 R, FSA 86 R, FSA 60 R and FSA 80 R the PolyCut blade heads are one to three decibels louder at the ear than the line heads, with sound power within a decibel. On the FSA 45, an older STIHL model with a built-in battery, the blades were three decibels quieter at the ear, 77 against 80, and seven lower in measured sound power. EGO's ST1530E manual shows the trade most plainly: its optional blade declares 76.5 dB(A) at the ear against 81.7 with line, but a guaranteed 98 against 96. Quieter for you, louder for the street.
Where the head clearly matters is runtime. STIHL USA rates its homeowner trimmers for up to twice as long with the plastic blade head: 25 against 50 minutes on an AK 10 for both the FSA 50 and FSA 57, 25 to 45 against 50 to 90 minutes on an AK 20 for the FSA 70 R, and 10 against 15 minutes on an AS 2 for the FSA 30. The FSA 30 manual says it directly: "Using a mowing head with mowing lines may shorten the battery runtime." For a short edging session, that can mean one battery instead of two.
Line size and STIHL's quiet line
STIHL's manuals list "round, quiet" or "round, low-noise" line for these heads: 1.6 mm for the FSA 50 and FSA 30, 1.6 or 2.0 mm for the FSA 57, and 2.0 or 2.4 mm for the FSA 70 R. Its FSA 45 declaration names the 1.6 mm "round, quiet" line as the condition of its figure. Worx uses 0.065 inch (1.65 mm) line on the WG163, Husqvarna 2.0 mm on the 520iLX's T25B head, EGO 2.4 mm twist line, and RYOBI's bump head takes .105 inch line.
No maker publishes figures by line size, so the data cannot say that thinner or rounder line is quieter. What the manuals do say is which line the declared figure assumes. Fit a heavier or differently shaped line and you are outside the condition the maker measured.
Runtime and how much edge a charge covers
STIHL prints how much lawn edge a charge covers, which for this job is more useful than minutes. By STIHL USA's figures, an AK 10 edges up to 4,101 feet with the FSA 50 and 2,050.5 feet with the FSA 57, an AK 20 up to 9,842.5 feet with the FSA 70 R, and an AS 2 up to 590.6 feet with the FSA 30. STIHL adds that the working times "are indicative and may vary depending on the application and operating mode".
Other makers quote minutes only. EGO gives the ST1511T "up to 45 minutes of run time" on its 2.5 Ah battery, RYOBI "Up to 67 minutes of runtime" for the RY402110 on a 6 Ah battery, and Husqvarna names no minutes for savE mode. None says which speed setting its minutes assume.
Weight, shaft and reach
Makers state weight under different conditions, so read these as a rough guide, all without a battery: STIHL's FSA 30 at 2.1 kg with its deflector and cutting attachment, Worx's WG163 at 2 kg on its European page, STIHL's FSA 57 at 2.7 kg with its cutting tool and deflector, the FSA 50 at 2.9 kg and the FSA 70 R at 3.2 kg with their heaviest heads, Husqvarna's 520iLX at 6.6 lb with its cutting head, the 110iL FLXi at 6.61 lb without cutting equipment, and EGO's ST1510E-T at 3.5 kg.
None of the makers here describes a curved shaft on a trimmer with a declared figure, so maker data cannot say whether a curved shaft changes what you hear. Several shafts adjust: STIHL gives the FSA 30 1,160 to 1,340 mm and the FSA 57 1,490 to 1,690 mm without the cutting attachment, and Worx calls the WG163's shaft telescoping. A longer shaft puts the head further from your ears, but no maker publishes a figure that isolates it.
Small sounds that carry
The Worx manual describes one noise worth knowing about at an early hour. Each time the WG163 starts from rest "it will advance about 0.25 inches of trimmer line", and "A 'clattering' noise will be heard when the lines hit the Line Cutter." The manual adds: "After about 5 seconds the line will be cut to the correct length and the noise will reduce as the motor gains full speed." Pressing the Command Feed button brings the same clatter. Fewer stops and starts along the side of the lot nearest the neighbors mean fewer of those moments.
If the edges are only half the job, our guide to the quietest battery lawn mowers applies the same neighbor-first ranking to the mowing.
Claims that cannot be ranked
Some quiet claims come without a figure, a distance or a standard. We list them here, apart from the declarations, and rank none of them.
- RYOBI sells the RY402110 as "Whisper Series - engineered to be 72% quieter than gas", "designed with a direct drive motor and a sound-defusing grass shield", and the RY40HPST02B as "Engineered to be 86% Quieter Than Gas". Neither page says which gas trimmer the percentage compares against, or prints a decibel figure.
- STIHL USA says of the FSA 60 R: "Quiet to use, can work without ear protection." STIHL's own FSA 60 R manuals recommend hearing protection. STIHL USA also tags the FSA 57, FSA 30, FSA 80 R and FSA 86 R "For use in noise-sensitive areas".
- Husqvarna says the 110iL FLXi's "low-noise performance makes it ideal for residential areas with strict noise ordinances, allowing you to work without disturbing your neighbors."
- Toro sums up its 60 V system on the 51830T page as "Easier. Faster. Cleaner. Greener. Quieter.", with no figure.
The STIHL, Husqvarna, Worx and EGO manuals we read all recommend hearing protection anyway. Husqvarna's puts it this way: "In general, battery powered products are relatively quiet but damage can result from a combination of noise level and long usage."
How we chose
We started from the battery trimmers in our main trimmer guide and the STIHL, Husqvarna and EGO brand pages, and re-opened every maker source: STIHL's international and North American manuals on its document server and STIHL USA's product data, Husqvarna's US pages and manuals, Worx's US page and manual and its European page and manual, EGO's European manuals and US and UK pages, and the RYOBI, Toro, DEWALT and Milwaukee US pages. We ranked guaranteed sound power only against guaranteed sound power, ear figures only within the standard the maker names, and kept claims without a stated basis out of both. A European figure appears against a US model only where the maker's numbering shows they are the same tool, and we say so each time.
We did not measure any of these trimmers. Every figure here is the maker's own, quoted as published with its standard, uncertainty and source where the maker gives them, and where a maker publishes nothing for a model or a setting, we say so rather than estimate.
