Finding the right 20-inch mower blade is essential for a crisp, even lawn and smooth mower operation. This guide highlights five top options that fit common 20″ decks and are aligned with typical replacement needs. Each blade is evaluated for who it’s best for, why it stands out, and any practical limits. Ideal buyers include homeowners with standard 20″ walk-behind mowers seeking longer-lasting edge retention, easy sharpening, or a quick compatibility check. Use the quick-reference table to compare essentials at a glance.
Product snapshot: The following table summarizes the five featured blades, their compatibility highlights, and the key benefit each offers for different mowing tasks. This helps buyers quickly assess which blade matches their mower model and cutting goals.
| Product | Best For | Key Benefit | Center Hole / Width |
|---|---|---|---|
| Fourtry 942-0640 Blade | MTD/Yard Machines 20″ decks | Longer-lasting sharpness with protective finish | 1″ x 3/4″ / 2 1/4″ width |
| KOFINAM 1 Pack Replacement Blade | Oregon-based compatible blades users | Compact replacement aligned with popular part numbers | 1″ x 3/4″ / 2 1/4″ width |
| Greenworks Replacement Blades (20″) | Greenworks 20″ mowers owners | Set includes right/left blades; heat-treated for sharpness | 2 1/4″ width |
| Grasscool 2105300125A Replacement Blade | Hyper Tough/Murray 20″ deck owners | Oval center hole variant for compatibility | 1″ x 3/4″ center / 2 1/8″ center-to-center |
| Stens 355-101 Standard Blade | Hyper Tough/MNA152701 compatible decks | Standard blade with precise dimensions | 1″ x 3/4″ / 2 1/8″ spacing |
Fourtry 942-0640 Blade Compatible With 20″ Deck
Reference: Compatible with 20″ Deck MTD Yard Machines Walk Behinds, 20″ MTD Columbia Walk Behinds, and 20″ MTD Bolens Walk Behinds. Replaces OEM 942-0640, 742-0640, 490-100-M115. Features precision-cutting edges and a protective finish. Best for homeowners upgrading from worn OEM blades who want durable edge retention. Caution: verify exact deck model to avoid misfit. Selected for long-lasting performance and compatibility with multiple 20″ models.
KOFINAM 1 Pack Replacement Blade
Reference: Replacement part number 2105300125A compatibility with MNA152505 and MNA152701/516 variants. Best for buyers who need a straightforward 20″ blade replacement aligned with Hyper Tough/Murray platforms. Choose this if you confirm part numbers match, as it notes specific compatibility. Limitation: not created by Hyper Tough, so verify brand alignment with your mower deck.
Greenworks Replacement Lawn Mower Blades (20″)
Reference: Includes a right and left blade set for Greenworks 20″ mowers with heat-treated steel for sharp, precise cuts. Best for Greenworks owners seeking an official-like replacement with dependable performance. Limitation: designed for specific Greenworks models; check your mower’s model number to ensure compatibility.
Grasscool 2105300125A 20 Inch Blade
Reference: Blade replacement for Hyper Tough Murray 2105300125A; compatible with MNA152505/701/516. Center hole: 1″ x 3/4″; length 20″; width 2 1/4″; thickness 0.125″. Best for buyers who need an oval-centered variant and a direct fit for Hyper Tough/Murray decks. Caution: verify the exact center-hole pattern before ordering to avoid misfit with non-oval patterns.
Stens 355-101 Standard Blade
Reference: Standard blade compatible with Hyper Tough and MNA152701 variants; 20″ length, 0.125″ thickness, 2 1/4″ width, center hole 1″ x 3/4″. Best for users who want a widely compatible, standard-size blade with predictable fit. Limitation: ensure your mower’s center-hole pattern matches the listed dimensions to avoid mounting issues.
Buying Guide
What should you consider when choosing a 20-inch mower blade?
- Deck compatibility: Confirm the exact mower model and the OEM replacement numbers to avoid misfits. Some blades target specific brands (MTD, Hyper Tough, Murray, Greenworks) and may not fit all 20″ decks.
- Center-hole alignment: The center-hole size and pattern (often 1″ x 3/4″ or oval variants) affect mounting. Measure your existing blade before purchasing if possible.
- Material and hardness: Look for heat-treated steel or blades marketed as durable and sharper for longer. This helps reduce frequency of sharpening and blade chatter during mowing.
- Two-blade sets vs single blades: Some manufacturers offer left-right blade pairs; these can simplify replacement and ensure balanced cutting over time.
- Durability vs cost: Higher durability blades can cost more upfront but may save time and maintenance in the long run. Weigh your mowing frequency and terrain against price.
- Maintenance and replacement cadence: Consider how often you’ll need to sharpen or replace blades depending on grass conditions and debris exposure (rocks, roots, thick weeds).
- Safety and handling: Some blades feature protective finishes to reduce accidental contact during handling. Always unplug or power down equipment before changing blades.
Frequently Asked Questions
- What is the standard blade size for most 20″ mowers?
Answer: Most 20″ mowers use blades around 20 inches in length with widths of about 2 1/4 inches and a center hole pattern of 1″ x 3/4″ or a common oval variant, but always verify your model’s exact spec before purchasing. - Can I use any 20″ blade on my mower?
Answer: No. Compatibility depends on deck model, center-hole pattern, and blade width. Check the OEM part numbers and your mower’s manual to confirm fit. - How often should I replace or sharpen a 20″ mower blade?
Answer: Replacement or sharpening frequency depends on mowing conditions and blade wear. Blades should be sharpened when they become dull or pitted; replacement is advised when chips or cracks appear. - Are there safety considerations when installing a new blade?
Answer: Yes. Always disconnect power, secure the blade properly, and wear protective gloves. Confirm blade orientation and ensure fasteners are tightened to the manufacturer’s torque specification.