10 Best Solder for Electronics (October 2026)

Most failed solder joints start at the spool, not the iron. Wire that is too thick floods a pad and bridges neighboring pins. Wire that is too thin takes forever to feed onto a heavy terminal. An alloy that melts over a wide range leaves a grainy, disturbed joint if the board moves while it cools. Flux content matters as well, because too little leaves oxidized joints and too much leaves a sticky residue around every pad. The Best Solder for Electronics depends on the alloy, the wire diameter and the flux core you pair with the parts on your bench.

The short answer: the MAIYUM 63/37 0.8mm Solder is the most balanced everyday choice for circuit boards and general repair. The Kester 24-6040-0027 Solder suits buyers who want a recognized brand for Arduino-style boards and heat-sensitive parts. The HGMZZQ 60/40 0.8mm Solder suits small electronics and hobby work with a slightly richer flux core. The rest of the list covers thinner and thicker wire, 100g spools, 1 lb Kester spools and a compact dispenser tube.

TL;DR: top picks at a glance

• Best overall: the MAIYUM 63/37 0.8mm Solder, a 63/37 alloy with 1.8% flux that melts at 183 °C in a 0.8mm wire.
• Best for Arduino and SMD work: Kester 24-6040-0027 Solder, a 0.031-inch wire that flows quickly and gives repeatable joints on small boards.
• Best for small electronics: HGMZZQ 60/40 0.8mm Solder, a 60/40 alloy with a 2.2% flux core for stereos, headsets, toys and control boards.
• Best for fine board repairs: WYCTIN 60/40 0.6mm Solder, the thinnest general-purpose wire in the list at 0.6mm.

Best Solder for Electronics Comparison (October 2026)

#	Product	Best for	Alloy	Diameter	Amount
1	MAIYUM 63/37 0.8mm Solder	General PCB repair	63/37	0.8mm	50g
2	Kester 24-6040-0027 Solder	Arduino and SMD	Not listed	0.031 in	1 lb
3	HGMZZQ 60/40 0.8mm Solder	Small electronics	60/40	0.8mm	50g
4	WYCTIN 60/40 0.6mm Solder	Fine board repairs	60/40	0.6mm	50g
5	TOWOT 63/37 1.0mm Solder	Through-hole joints	63/37	1.0mm	50g
6	AUSTOR 60/40 1.5mm Solder	Wires and terminals	60/40	1.5mm	100g
7	YI LIN 60/40 100g Solder	Home repair stock	60/40	0.6mm (0.8mm also stated)	100g
8	Kester 24-6337-0027 Solder	Everyday bench use	63/37	0.031 in	1 lb
9	Kester 44 0.020-Inch Spool	Fine-pitch work	63/37	0.020 in	1 lb
10	Kester 44 1-Ounce Tube	Occasional repairs	63/37	0.031 in	1 oz

1. MAIYUM 63/37 0.8mm Solder: Best Eutectic Rosin Core Solder for PCB Repair

• Alloy: 63% tin, 37% lead
• Wire Diameter: 0.8mm (0.0315 inch)
• Flux Content: 1.8% rosin core
• Melting Point: 183 °C (361 °F)
• Spool Weight: 50g (about 0.11 lb)

Pros:

• The 63/37 alloy melts and freezes at a single temperature, 183 °C, so joints set cleanly without a pasty stage.
• The 0.8mm diameter handles most through-hole pads and larger SMD pads without bridging.
• The 1.8% flux core is modest, which keeps residue light around fine pins.
• The compact 50g spool is small enough to keep in a pocket or a repair kit.

Cons:

• The 0.8mm wire is too thick for 0402-size parts and tight-pitch QFP pins.
• A 50g spool runs out quickly for anyone soldering most weekends.
• It contains lead, so it needs ventilation and hand washing after use.

Best for: Hobbyists and repair technicians who want one all-round spool for circuit boards, cable repair and small appliance work.

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The MAIYUM 63/37 0.8mm Solder earns the top spot by getting the middle of the range right. A eutectic 63/37 alloy is the most forgiving choice for beginners, because a joint that is nudged while cooling is less likely to turn grainy. At 0.8mm it sits between the fine WYCTIN 60/40 0.6mm Solder and the heavier TOWOT 63/37 1.0mm Solder, which makes it workable on the widest range of boards.

It is also sold in a 0.8mm 100g version and a 0.6mm 50g version. Choose the 0.6mm option if your work is mostly surface-mount.

It is the wrong choice for heavy wiring and large terminals, where the AUSTOR 60/40 1.5mm Solder feeds more metal per second. It is also the wrong choice for bulk use, where the 1 lb Kester 24-6337-0027 Solder covers far more joints per spool.

2. Kester 24-6040-0027 Solder: Best 0.031-Inch Spool Solder for Arduino and SMD Work

• Wire Diameter: 0.031 inch
• Alloy: Not listed
• Flux Content: Not listed
• Item Weight: About 1 lb
• Label: Kester "Yellow" label

Pros:

• It flows quickly and gives repeatable results from joint to joint, which suits repetitive board work.
• The 0.031-inch diameter fits Arduino boards and shields well.
• It works on SMD parts and heat-sensitive jobs, where short dwell time at the pad matters.
• Joints from this wire are described as holding up for years without cracking or dulling.

Cons:

• The alloy ratio and flux percentage are not specified, so you cannot match it to a lead-free or eutectic requirement in advance.
• A 1 lb spool is more material than a casual hobbyist will use.
• The part number is a dense code that is easy to confuse with the other Kester entries.

Best for: Electronics builders who want a brand-name, general-purpose wire for microcontroller boards, shields and small surface-mount repair.

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The Kester 24-6040-0027 Solder stands out because its strengths are practical rather than specification-driven. It flows fast, melts readily and produces consistent joints, which matters more on a busy bench than a shaved fraction of a percent of flux. Its 0.031-inch wire is the same diameter as the Kester 24-6337-0027 Solder, so the two feel alike in use.

Its main limit is the missing spec sheet. A buyer who needs a confirmed 63/37 eutectic alloy should pick the MAIYUM 63/37 0.8mm Solder or the Kester 24-6337-0027 Solder instead. Anyone working on very fine pitch should step down to the 0.020-inch Kester 44 0.020-Inch Spool.

Because the wire is about 1 lb in weight, it works as long-term stock rather than a one-project buy. For a single repair, a 50g spool such as the HGMZZQ 60/40 0.8mm Solder is easier to justify.

3. HGMZZQ 60/40 0.8mm Solder: Best 2.2% Flux Solder for Small Electronics

• Alloy: 60% tin, 40% lead
• Wire Diameter: 0.8mm (0.031 inch)
• Flux Content: 2.2% rosin core
• Melting Point: Stated as 183 °C (361 °F)
• Spool Weight: 50g (1.76 oz)

Pros:

• The 2.2% flux core wets pads quickly, which helps on slightly oxidized components.
• It melts evenly with little smoke, so the work area stays clearer.
• It suits a broad list of jobs, including stereos, headsets, toys and control board repair.
• It has been used on guitar electronics and small component projects with good results.

Cons:

• The thinness of the 0.8mm wire gets mixed reactions, since some users want more metal per feed.
• The 60/40 alloy passes through a pasty stage, so the joint must stay still while it cools.
• The 50g spool is small for frequent use.

Best for: Hobbyists repairing consumer electronics, instruments and toys who prefer a higher flux core and a small spool.

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The HGMZZQ 60/40 0.8mm Solder is the closest rival to the number one pick, and the difference is chemistry. Its 2.2% flux core is richer than the 1.8% in the MAIYUM 63/37 0.8mm Solder, so it cleans and wets more aggressively, though it leaves slightly more residue. The 60/40 alloy also lacks the single melting point of 63/37, which makes it a little less forgiving for a shaky hand.

Buyers consider it good value for small electronics, and the melting and flow behavior is a regular point in its favor. It is the wrong choice for fine SMD work, where the WYCTIN 60/40 0.6mm Solder gives better control. It is also the wrong choice for anyone who wants the one-temperature behavior of a eutectic alloy, in which case the TOWOT 63/37 1.0mm Solder or MAIYUM fits better.

4. WYCTIN 60/40 0.6mm Solder: Best Thin-Gauge Solder for Fine Board Repairs

• Alloy: 60% tin, 40% lead
• Wire Diameter: 0.6mm (0.0236 inch)
• Flux Content: Not listed
• Melting Point: Stated as 183 °C (361 °F)
• Spool Weight: 50g (0.11 lb, 1.61 oz)

Pros:

• The 0.6mm wire lets you place a very small amount of solder, which reduces bridging on fine pins.
• It is suited to cable, TV, radio, stereo and toy repair as well as small household appliances.
• The thin wire melts quickly, so the iron tip spends less time on delicate pads.
• A thicker 1.2mm 50g version is also sold for jobs that need more metal.

Cons:

• The flux percentage is not specified.
• Thin wire is slow to feed on large joints, wires and shielding.
• The 50g spool is modest for regular use.

Best for: Repair hobbyists working on dense boards and small components who want tighter control over how much solder reaches the joint.

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The WYCTIN 60/40 0.6mm Solder is the pick when the board matters more than the speed. At 0.6mm it is thinner than the HGMZZQ 60/40 0.8mm Solder and the MAIYUM 63/37 0.8mm Solder, and the difference is clear on SMD pads and pin headers.

It is the wrong spool for chunky work. Splicing multi-strand wire or tinning a large lug is much faster with the AUSTOR 60/40 1.5mm Solder. Buyers who want the same fine diameter in a larger quantity should look at the YI LIN 60/40 100g Solder, though its diameter details are less clear. Those who need the finest wire of all should consider the 0.020-inch Kester 44 0.020-Inch Spool.

5. TOWOT 63/37 1.0mm Solder: Best 1.0mm Eutectic Solder for Through-Hole Joints

• Alloy: 63% tin, 37% lead
• Wire Diameter: 1.0mm
• Flux Content: 1.8%
• Spool Weight: 50g (about 0.11 lb)
• Finish: Silver, solid single-strand wire

Pros:

• The eutectic 63/37 alloy gives fast, clean joint formation at a single melting point.
• The 1.0mm diameter delivers more solder per second on larger pads and through-hole legs.
• It flows well and melts quickly, and it holds wires firmly once cooled.
• It is suited to circuit boards, TV and radio repair and household appliance work.

Cons:

• Some users find the wire smaller than they expected, so check the 1.0mm figure before buying.
• At 1.0mm it is too thick for fine-pitch SMD work.
• The 50g spool is small for large wiring projects.

Best for: Builders working mostly with through-hole kits and power boards who want a eutectic alloy in a slightly heavier wire.

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The TOWOT 63/37 1.0mm Solder shares its alloy and 1.8% flux with the MAIYUM 63/37 0.8mm Solder, so the main change is diameter. That makes it quicker on large pads but less precise on small ones. For a general-purpose bench spool the 0.8mm wire is more adaptable, which explains the ranking.

It is the wrong choice for tight-pitch boards, where the WYCTIN 60/40 0.6mm Solder is the better fit. It is also the wrong choice for terminal-heavy or thick-wire jobs, where the AUSTOR 60/40 1.5mm Solder delivers more metal in a pass.

6. AUSTOR 60/40 1.5mm Solder: Best Heavy-Gauge Solder for Wires and Terminals

• Alloy: 60% tin, 40% lead
• Wire Diameter: 1.5mm (0.059 inch)
• Flux Content: 2.0%
• Melting Range: 185 °C to 190 °C (365 °F to 374 °F)
• Spool Weight: 100g (0.22 lb)

Pros:

• The 1.5mm wire feeds a large volume of solder quickly onto big joints.
• The 100g spool holds twice the material of the 50g spools in this list.
• A stated melting range of 185 °C to 190 °C is an honest description of how 60/40 behaves.
• It is also sold in 0.6mm, 0.8mm and 1.2mm versions on 100g spools.

Cons:

• The 1.5mm wire is too heavy for circuit boards with small pads or fine pins.
• Large wire needs more heat from the iron to melt without cooling the tip.
• The 60/40 alloy has a short pasty stage, so joints need to stay still while setting.

Best for: Builders soldering audio cables, connectors and hobby wiring who need to fill thicker joints quickly.

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The AUSTOR 60/40 1.5mm Solder is a different tool from the PCB-focused spools above it. It is aimed at repair work where joint size is large and speed matters, and its 2.0% flux core falls between the MAIYUM and HGMZZQ figures.

The melting range is useful to know when setting an iron. A temperature just above 190 °C is the practical target, and a hotter tip helps when joining heavy stranded wire. It is also a sensible choice for hobby wiring at battery terminals, such as tinning leads that will later be clamped to one of the parts covered in a guide to battery terminals.

It is the wrong choice for anything delicate. Boards and small components are far better served by the MAIYUM 63/37 0.8mm Solder or the WYCTIN 60/40 0.6mm Solder.

7. YI LIN 60/40 100g Solder: Best 100g Fine-Wire Solder for Home Repair

• Alloy: 60% tin, 40% lead
• Wire Diameter: 0.6mm in the product name, with 0.8mm also stated
• Flux Content: 1.8%
• Spool Weight: 100g (0.22 lb, 3.52 oz)
• Flux Type: Rosin core with low residue

Pros:

• The 100g quantity gives twice the wire of the 50g spools from MAIYUM, HGMZZQ and WYCTIN.
• The 1.8% flux core keeps residue light around components.
• It suits cable, TV, radio and stereo repair, as well as general circuit work.
• It is aimed at fast joint formation with a low melting point.

Cons:

• The diameter is stated as both 0.6mm and 0.8mm, so the exact gauge is unclear.
• The melting point is not specified.
• The 60/40 alloy is less forgiving than 63/37 when a joint moves during cooling.

Best for: Home repairers who want a larger fine-gauge spool for occasional electronics and cable work.

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The YI LIN 60/40 100g Solder appeals mainly on quantity. Its 100g spool matches the AUSTOR 60/40 1.5mm Solder in weight but uses a much finer wire, which is the more useful combination for board work.

The diameter inconsistency holds it back. A buyer who needs a guaranteed 0.6mm wire is safer with the WYCTIN 60/40 0.6mm Solder, and one who needs a confirmed 0.8mm is safer with the MAIYUM 63/37 0.8mm Solder.

8. Kester 24-6337-0027 Solder: Best 1 lb Core 66 Solder for Bench Stock

• Alloy: 63% tin, 37% lead
• Wire Diameter: 0.031 inch
• Core Size: 66 (3.3% flux)
• Spool Weight: 1 lb per spool
• Label: Kester "Yellow" label

Pros:

• The 1 lb spool lasts through thousands of joints, so it works as long-term bench stock.
• The 63/37 eutectic alloy melts and sets at a single temperature.
• Core 66 carries a generous 3.3% flux for good wetting on older parts and wire.
• The 0.031-inch wire suits both boards and general electronics work.

Cons:

• The 3.3% flux core leaves more residue than the 1.8% cores from MAIYUM or TOWOT.
• The 1 lb spool is far more than a casual hobbyist needs.
• It contains lead, so ventilation and washing are essential.

Best for: Frequent solderers and small workshops who want a consistent, brand-name 63/37 stock spool.

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The Kester 24-6337-0027 Solder is the practical choice for heavy use. It pairs the eutectic alloy of the MAIYUM 63/37 0.8mm Solder with a larger quantity and a more active flux. The extra flux wets stubborn surfaces better but means boards often need a cleaning pass afterward.

It is the wrong choice for a one-off repair, where a 50g spool such as the TOWOT 63/37 1.0mm Solder is more sensible. It is also not ideal for fine-pitch work, where the 0.020-inch Kester 44 0.020-Inch Spool uses the same alloy in a thinner wire.

9. Kester 44 0.020-Inch Spool: Best 0.50mm Solder for Fine-Pitch Work

• Alloy: 63% tin, 37% lead
• Wire Diameter: 0.020 inch (0.50mm)
• Core Size: 66 (3.3% flux), high-activity rosin
• Spool Weight: 1 lb
• Joint Finish: Bright, shiny joints after reflow

Pros:

• At 0.50mm it is the thinnest wire in the list, ideal for fine-pitch and small SMD pads.
• The eutectic 63/37 alloy sets cleanly at a single temperature.
• The high-activity rosin core wets a wide variety of metal surfaces.
• It leaves bright, shiny joints, which makes visual inspection easier.

Cons:

• The 3.3% flux core leaves noticeable residue that usually needs cleaning.
• A 1 lb spool of fine wire is a large commitment for occasional use.
• The fine wire is slow to feed on larger joints.

Best for: Technicians and advanced hobbyists doing fine-pitch surface-mount work who will use a full spool over time.

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The Kester 44 0.020-Inch Spool is described as an industry standard, and its fine diameter is the reason to buy it. It reaches pads the 0.6mm WYCTIN 60/40 0.6mm Solder would flood, and it shares the 63/37 alloy and core 66 flux of the Kester 24-6337-0027 Solder.

Because of the high-activity flux, cleaning is part of the process. Cleaning boards with an industrial ultrasonic cleaner is one way to remove baked-on residue. It is the wrong spool for beginners or for through-hole kits, where the MAIYUM 63/37 0.8mm Solder is easier to use.

10. Kester 44 1-Ounce Tube: Best Dispenser Tube Solder for Occasional Repairs

• Alloy: 63% tin, 37% lead
• Wire Diameter: 0.031 inch
• Flux Type: RMA rosin
• Quantity: 1-ounce dispenser tube, roughly 24 feet of wire
• Packaging: Dispenser tube

Pros:

• The 1-ounce tube is easy to store in a toolbox or drawer and keeps the wire tidy.
• Around 24 feet of wire covers many small repairs.
• The Kester 44 core is well known for electronics work.
• The 63/37 alloy provides clean, single-temperature joints.

Cons:

• A 1-ounce quantity is used up quickly if you solder regularly.
• Diameter details are given inconsistently, so confirm the 0.031-inch gauge before relying on it for fine-pitch work.
• Residue from the active flux may need cleaning for neat results.

Best for: Occasional repairers who want a small amount of well-known electronics solder without committing to a full spool.

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The Kester 44 1-Ounce Tube is the lowest-commitment way to get genuine Kester 44 solder. It uses the same family of wire as the Kester 24-6337-0027 Solder, but in a compact dispenser that suits a single project.

It ranks last because of quantity and clarity. Regular solderers will find the 1 lb Kester 24-6337-0027 Solder far more economical per joint, while buyers who want a confirmed small-gauge wire should pick the Kester 44 0.020-Inch Spool.

Buyer's Guide: How to Choose the Right Solder

Choosing solder for electronics is a balance between joint size, alloy behavior and cleanup. A thin wire gives control but feeds slowly, a thick wire fills joints fast but floods small pads, and a richer flux wets better but leaves more residue.

Before choosing, check these project details:

• Pad and pin size: Match wire diameter to the smallest part you solder most often.
• Alloy preference: Decide between eutectic 63/37 and the more common 60/40.
• Flux strength: Higher flux wets better but leaves more residue to clean.
• Quantity: A 50g spool suits occasional work, while a 1 lb spool suits regular use.
• Safety: Every spool here contains lead, so plan for ventilation and hand washing.

Alloy Type

The 63/37 alloy is eutectic, meaning it melts and solidifies at one temperature, 183 °C. The MAIYUM 63/37 0.8mm Solder, TOWOT 63/37 1.0mm Solder and the Kester 63/37 spools use it. This makes joints forgiving, because there is no pasty stage in which a shaking hand can disturb the metal.

The 60/40 alloy used by HGMZZQ 60/40 0.8mm Solder, WYCTIN 60/40 0.6mm Solder, AUSTOR 60/40 1.5mm Solder and YI LIN 60/40 100g Solder melts across a narrow range, as the AUSTOR figure of 185 °C to 190 °C shows. It works well but asks for a steadier hand. Neither alloy should be used on a lithium cell such as an 18650 battery, where prolonged heat risks damage and tab-welding is the safer method.

Wire Diameter

Diameter controls how much solder you deliver per second. The Kester 44 0.020-Inch Spool at 0.50mm and the WYCTIN 60/40 0.6mm Solder suit small SMD pads and tight pins. The 0.8mm wires from MAIYUM and HGMZZQ are the best all-round compromise.

At the heavy end, the TOWOT 63/37 1.0mm Solder and AUSTOR 60/40 1.5mm Solder fill larger joints quickly. A good rule is to pick a diameter no larger than the smallest pad you work on regularly, since you can always feed thin wire for longer.

Flux Core and Residue

Flux cleans oxidation and helps solder wet the metal. The MAIYUM 63/37 0.8mm Solder and TOWOT 63/37 1.0mm Solder carry 1.8%, the AUSTOR 60/40 1.5mm Solder carries 2.0%, and the HGMZZQ 60/40 0.8mm Solder carries 2.2%. The Kester core 66 spools reach 3.3%.

Higher flux means better wetting on old or dull parts, but it also leaves more residue that should be cleaned from finished boards. For tidy results with core 66 wire, plan on a cleaning step after soldering.

Spool Size and Packaging

Spool size is about how often you solder. The 50g spools suit a toolbox, the 100g YI LIN 60/40 100g Solder and AUSTOR 60/40 1.5mm Solder suit regular home use, and the 1 lb Kester 24-6040-0027 Solder, Kester 24-6337-0027 Solder and Kester 44 0.020-Inch Spool suit workshops.

The Kester 44 1-Ounce Tube sits at the other extreme, trading quantity for convenience. Buying more than you will use rarely helps, since leftover wire can oxidize over time if stored badly.

Frequently Asked Questions About Solder for Electronics

Is 63/37 or 60/40 Solder Better for Electronics?

For most electronics work, 63/37 is the easier choice because it melts and sets at a single temperature. The MAIYUM 63/37 0.8mm Solder shows this advantage well on boards. The 60/40 alloy, such as the HGMZZQ 60/40 0.8mm Solder, still works well if you keep the joint still while it cools.

What Diameter Solder Should I Use for Circuit Boards?

A diameter of 0.6mm to 0.8mm covers most circuit board work. The WYCTIN 60/40 0.6mm Solder suits fine pads, and the MAIYUM 63/37 0.8mm Solder suits general boards. For very fine pitch, the 0.50mm Kester 44 0.020-Inch Spool is thinner still.

Can I Use Rosin Core Solder on Electronics?

Yes, rosin core is the standard type for electronics, and every product in this list has a rosin-based flux core. The Kester 44 1-Ounce Tube uses an RMA rosin, while the Kester core 66 spools use a more active rosin with 3.3% flux. Avoid acid-core plumbing solder on boards, since its residue is corrosive.

Is Leaded Solder Safe to Use?

Leaded solder is safe enough for hobby use if you work in a ventilated space and wash your hands afterward. All ten products here, including the AUSTOR 60/40 1.5mm Solder and TOWOT 63/37 1.0mm Solder, contain lead and carry a warning. Keep it away from food areas and children.

How Much Solder Do I Need to Buy?

A 50g spool such as the WYCTIN 60/40 0.6mm Solder covers many small repairs. Regular solderers will get more from a 100g spool like the YI LIN 60/40 100g Solder or a 1 lb spool like the Kester 24-6337-0027 Solder. For a single project, the Kester 44 1-Ounce Tube is enough.

Do I Need to Clean Flux Residue After Soldering?

Light residue from 1.8% cores like the TOWOT 63/37 1.0mm Solder is often acceptable on hobby projects. Heavier residue from the 3.3% Kester core 66 spools is best removed for a neat, reliable finish. Isopropyl alcohol and a brush handle most cases.

Final Verdict: Which Solder Should You Buy?

Best Solder for Electronics for most buyers start with MAIYUM 63/37 0.8mm Solder: a eutectic 63/37 alloy with 1.8% flux, a 0.8mm wire and a 183 °C melting point, supplied on a pocket-sized 50g spool. Its main weakness is that 0.8mm is too thick for the finest SMD work, and 50g runs out quickly for frequent users.

For other uses, the Kester 24-6040-0027 Solder suits Arduino boards and SMD repair with a trusted brand, though its alloy and flux are not specified. The HGMZZQ 60/40 0.8mm Solder is the pick for small electronics that benefit from a 2.2% flux core. The TOWOT 63/37 1.0mm Solder gives a eutectic alloy in a heavier wire for through-hole work.

The specialist picks cover narrower needs. The WYCTIN 60/40 0.6mm Solder and Kester 44 0.020-Inch Spool handle fine pitch, the AUSTOR 60/40 1.5mm Solder handles heavy wire and terminals, the YI LIN 60/40 100g Solder offers a larger home-repair spool, the Kester 24-6337-0027 Solder serves as 1 lb bench stock, and the Kester 44 1-Ounce Tube suits occasional jobs. If you are still undecided, buy the MAIYUM 0.8mm spool first, then add a thinner or thicker wire once your own projects show which one you reach for.