Buying Guide
The Best Thermal Paste Under $20
Five thermal pastes ranked on tube size and amount, where the Duronaut 6g has the largest tube size; the NT-H2 is the cheapest route in.
By The PC Journal editorial team
12 min read5 products evaluated
Between $10 and $20, pastes add kits, larger tubes or formulas built against pump-out. Every pick sits in that range, ordered by tube size.
Rankings weigh amount, compound and electrically non-conductive as the makers state them; if a maker skips compound, the guide says so rather than guess, since we have not benched them.
Quick Picks
Our 5 recommendations at a glance. Tap a pick for the full verdict.
Largest Tube Size
Thermal Grizzly Duronaut (6g)
The largest tube size here (6g).
Best for: Buyers who put tube size first.
Our take Check price for Thermal Grizzly Duronaut (6g) (opens in a new tab)
Zinc Oxide Compound
Corsair XTM50 (5g)
A zinc oxide compound.
Best for: Buyers who want a zinc oxide compound.
Our take Check price for Corsair XTM50 (5g) (opens in a new tab)
A Syringe In the Box
Thermal Grizzly Hydronaut (3.9g)
A syringe in the box.
Best for: Buyers who want a syringe in the box.
Our take Check price for Thermal Grizzly Hydronaut (3.9g) (opens in a new tab)
Also Consider
Noctua NT-H2 (3.5g)
A recommended usage time of up to five years on the CPU.
Best for: Buyers who want recommended usage time of up to five years on the CPU.
Our take Check price for Noctua NT-H2 (3.5g) (opens in a new tab)
Strong Alternative
Noctua NT-H2 AM5 Edition (3.5g)
An NA-TPG1 guard that keeps paste out of the AM5 heatspreader's cut-outs.
Best for: Buyers who want NA-TPG1 guard that keeps paste out of the AM5 heatspreader's cut-outs.
Our take Check price for Noctua NT-H2 AM5 Edition (3.5g) (opens in a new tab)
Our Picks
Largest Tube Size1 of 5
Thermal Grizzly Duronaut (6g) on Amazon (opens in a new tab)
Duronaut is Thermal Grizzly's durability-focused paste, using aluminium and zinc oxide particles to minimise pump-out.
Best for
- Buyers who put tube size first.
Skip if
- Skip it if price comes first: the NT-H2 cost less when we checked.
Why we like it
The 6g tube comes with a TG Spatula Pro and suits hot CPUs you do not want to remount often. Its 6g tube size is the largest here; the XTM50 comes next at 5g. It is the only pick here with an a TG Spatula Pro in the box; the Hydronaut has an a syringe in the box instead.
It also comes with a paste that does not harden over time. Clean off old paste with isopropyl alcohol first, then apply a pea-sized dot or a thin line on the heatspreader; on large Intel chips an X or a line covers the longer die better. Only the Hydronaut came close to it on price at the time of writing; it cost the most of the 5 picks.
Key dimensions & specs
- Amount: 6g
- Compound: Aluminium and zinc oxide particles
- Electrically non-conductive: Yes
- In the box: a TG Spatula Pro
Pros
- 6g is enough for several applications
- Aluminium and zinc oxide particles formula
- Electrically non-conductive, so spills are harmless
- Includes a TG Spatula Pro
Cons
- Costs more than the NT-H2 at the time of writing
Zinc Oxide Compound2 of 5
Corsair XTM50 (5g) on Amazon (opens in a new tab)
XTM50 is a zinc-oxide, non-conductive paste with a stencil and spreader in the box, which takes the guesswork out of coverage.
Best for
- Buyers who want a zinc oxide compound.
Skip if
- Skip it if price comes first: the NT-H2 cost less when we checked.
Why we like it
Its low viscosity fills fine surface channels, and Corsair says it contains no volatile compounds. On tube size it sits mid-pack at 5g: the Duronaut 6g comes in at 6g, and the NT-H2 AM5 comes in at 3.5g. It also offers zero volatile compounds, by the maker's claim.
Clean off old paste with isopropyl alcohol first, then apply a pea-sized dot or a thin line on the heatspreader; on large Intel chips an X or a line covers the longer die better. It also brings 5g is enough for several applications. When we checked, only the NT-H2 AM5 and cheaper picks cost less, and the Hydronaut cost more.
Key dimensions & specs
- Amount: 5g
- Compound: Zinc oxide
- Electrically non-conductive: Yes
- In the box: an application stencil and spreader
Pros
- 5g is enough for several applications
- Electrically non-conductive, so spills are harmless
- Includes an application stencil and spreader
- Low-viscosity compound that fills fine surface channels
Cons
- Costs more than the NT-H2 at the time of writing
A Syringe In the Box3 of 5
Thermal Grizzly Hydronaut (3.9g) on Amazon (opens in a new tab)
Hydronaut is Thermal Grizzly's value-oriented enthusiast paste, rated at a thermal resistance of 0.0076 K/W.
Best for
- Buyers who want a syringe in the box.
Skip if
- Price-first buyers should look at the NT-H2, which cost less when we checked.
Why we like it
It comes in a syringe for precise placement and, by the maker's claim, does not harden over time. Its 3.9g tube size ranks third of 5 here, behind the Duronaut 6g (6g) and ahead of the NT-H2 AM5 (3.5g). You get an a syringe in the box here, which sets it apart from the NT-H2 and its a three cleaning wipes in the box.
Clean off old paste with isopropyl alcohol first, then apply a pea-sized dot or a thin line on the heatspreader; on large Intel chips an X or a line covers the longer die better. Before buying, weigh one limit: costs more than the NT-H2 at the time of writing.
Key dimensions & specs
- Amount: 3.9g
- In the box: a syringe
Pros
- Includes a syringe
- Maker-rated thermal resistance of 0.0076 K/W
- Formula that does not harden, by the maker's claim
- Tube size of 3.9g, ahead of the NT-H2
Cons
- Costs more than the NT-H2 at the time of writing
Also Consider4 of 5
Noctua NT-H2 (3.5g) on Amazon (opens in a new tab)
NT-H2 comes with three cleaning wipes and needs no spreading.
Best for
- Buyers who want recommended usage time of up to five years on the CPU.
Skip if
- Look at the others if this bothers you: tube size of 3.5g, behind the Duronaut 6g (6g).
Why we like it
Noctua rates it for up to five years on the CPU, which suits builders who set it and forget it. It matches the NT-H2 AM5 on tube size (3.5g). You get a three cleaning wipes in the box here, which sets it apart from the Hydronaut and its an a syringe in the box.
It also offers a recommended usage time of up to five years on the CPU and enough for around 3 to 20 applications. Clean off old paste with isopropyl alcohol first, then apply a pea-sized dot or a thin line on the heatspreader; on large Intel chips an X or a line covers the longer die better. Do not pre-spread it; let the cooler's mounting pressure distribute it. The main gap: tube size of 3.5g, behind the Duronaut 6g (6g). If that matters, the Duronaut 6g comes in at 6g.
Key dimensions & specs
- Amount: 3.5g
- In the box: three cleaning wipes
- Application: No need to spread before mounting
Pros
- Includes three cleaning wipes
- Recommended usage time of up to five years on the CPU
- Enough for around 3 to 20 applications
Cons
- Tube size of 3.5g, behind the Duronaut 6g (6g)
Strong Alternative5 of 5
Noctua NT-H2 AM5 Edition (3.5g) on Amazon (opens in a new tab)
This NT-H2 edition adds a guard that keeps paste out of the cut-outs around an AM5 heatspreader, a real annoyance when repasting Ryzen 7000 and 9000 chips.
Best for
- Buyers who want NA-TPG1 guard that keeps paste out of the AM5 heatspreader's cut-outs.
Skip if
- Skip it if tube size matters most to you; the Duronaut 6g offers 6g.
Why we like it
It also comes with three cleaning wipes. The guard sits around an AM5 chip during application and lifts away, leaving the heatspreader cut-outs clean. Noctua rates the paste for up to five years on a CPU.
On tube size it ties with the NT-H2 at 3.5g. You also get the second generation of Noctua's NT-H1. Clean off old paste with isopropyl alcohol first, then apply a pea-sized dot or a thin line on the heatspreader; on large Intel chips an X or a line covers the longer die better. It gives ground on tube size, where the Duronaut 6g comes in at 6g.
Key dimensions & specs
- Amount: 3.5g
- Rated service life: up to 5 years
- Applications per tube: About 3 to 20
- In the box: an AM5 paste guard and three cleaning wipes
Pros
- Maker-rated for up to 5 years without reapplying
- Includes an AM5 paste guard and three cleaning wipes
- NA-TPG1 guard that keeps paste out of the AM5 heatspreader's cut-outs
- The second generation of Noctua's NT-H1
Cons
- Tube size trails the Duronaut 6g (6g)
How We Chose
Each pick was assessed across 4 criteria weighted for real-world use.
- Safety
- We checked that each paste is listed as electrically non-conductive.
- Durability
- We looked for maker claims on pump-out and long-term stability.
- Application
- We noted spreaders, wipes and the maker's application guidance.
- Value
- We compared tube sizes and what comes in the box.
What to Look for in a Thermal Paste Under $20
Key buying criteria so you get the right fit the first time.
Durability matters on hot CPUs
Some pastes pump out or dry over thermal cycles. Pastes built for long-term stability suit high-power CPUs you do not want to remount often.
Buy the amount you will use
One large CPU uses about 0.2g to 0.5g. A 1g tube covers a couple of builds; 4g or more suits regular remounts or several machines.
Check the rated service life
Some makers state how long the paste can stay on a CPU before it needs replacing, from about five years to eight. A longer rating suits a PC you won't open often.
Differences between good pastes are small
Among reputable pastes, temperatures usually differ by a few degrees at most. Mounting pressure and application matter as much as the paste.
Treat W/mK figures with care
Makers measure conductivity under their own conditions, so a higher W/mK number on the box does not always mean lower temperatures in a PC. Compare pastes from the same test source instead.
Thicker pastes are harder to spread
High-performance pastes are often thick. Warming the tube in your hand makes them easier to apply.
How to Choose a Thermal Paste Under $20
By priority
| Priority | Consider | Why |
|---|---|---|
| Buyers who put tube size first | Duronaut 6g | The largest tube size here (6g) |
| Buyers who want a zinc oxide compound | XTM50 | A zinc oxide compound |
| Buyers who want a syringe in the box | Hydronaut | A syringe in the box |
| Buyers who want recommended usage time of up to five years on the CPU | NT-H2 | A recommended usage time of up to five years on the CPU |
| Buyers who want NA-TPG1 guard that keeps paste out of the AM5 heatspreader's cut-outs | NT-H2 AM5 | An NA-TPG1 guard that keeps paste out of the AM5 heatspreader's cut-outs |
Scroll sideways to see every column.
Key specs side by side
Figures as each maker states them.
| Paste | Amount | Compound | Electrically non-conductive | In the box |
|---|---|---|---|---|
| Duronaut 6g | 6g | Aluminium and zinc oxide particles | Yes | a TG Spatula Pro |
| XTM50 | 5g | Zinc oxide | Yes | an application stencil and spreader |
| Hydronaut | 3.9g | Not listed | Not listed | a syringe |
| NT-H2 | 3.5g | Not listed | Not listed | three cleaning wipes |
| NT-H2 AM5 | 3.5g | Not listed | Not listed | an AM5 paste guard and three cleaning wipes |
Scroll sideways to see every column.
Frequently Asked Questions
Which of these thermal pastes has the largest tube size?
The Duronaut 6g, at 6g. The XTM50 follows at 5g, while the NT-H2 AM5 has 3.5g.
What is the least I can spend on one of these thermal pastes?
That was the NT-H2 at our last check; if you can stretch, the NT-H2 AM5 is the next step up and the Duronaut 6g the priciest.
Is the paste that comes with my cooler good enough?
Usually yes. Aftermarket paste helps most when remounting or when the included paste has run out.
Does thermal paste expire in the tube?
It can separate or thicken after a few years in storage. Noctua, for example, recommends using its paste within three years of purchase.
Should I spread the paste or let the cooler do it?
Either works if the layer is thin and even. Some pastes, such as ARCTIC's MX-7, are designed to be pressed out by the cooler rather than spread.
Bottom Line
Our first pick is the Duronaut 6g, chosen for the largest tube size here (6g). Look at the XTM50 for a zinc oxide compound, the Hydronaut for a syringe in the box and the NT-H2 for a recommended usage time of up to five years on the CPU if those matter more to you.
Paying more buys durability and extras more than lower temperatures.