GLM 4.7 vs Mercury 2.5 Preview

Z.ai · China  |  Inception Labs · US · Updated June 2026

Quick verdict

Pick GLM 4.7 for genuinely permissive open weights — an mit-licensed 358b mixture-of-experts with no commercial restrictions or strong agentic coding for the price — 73.8% on swe-bench verified undercut most closed frontier models at launch. Pick Mercury 2.5 Preview for very high inference throughput (1,107 tok/s) via diffusion-based parallel token generation or coding accuracy (95.7%, 91st percentile among cost-optimized models). Choose GLM 4.7 if you need self-hosting or data privacy; Mercury 2.5 Preview if you want a managed API.

GLM 4.7 (Z.ai, China) and Mercury 2.5 Preview (Inception Labs, US) line up two different AI ecosystems against each other — a comparison that is as much about cost philosophy and openness as raw capability. GLM 4.7 is an MIT-licensed 358B open mixture-of-experts with strong 73.8% SWE-Bench Verified coding — but two generations behind GLM 5.2. Mercury 2.5 Preview is inception Labs' August 31, 2026 diffusion-based language model preview, refining tokens in parallel for roughly 10x the throughput of comparable autoregressive models at cost-optimized-tier quality. They diverge most on price, context window and open vs. closed weights — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecGLM 4.7Mercury 2.5 Preview
ProviderZ.ai (China) Inception Labs (US)
ReleasedDecember 22, 2025 August 31, 2026
Context window200K (~304 pages) 260K tokens (~390 pages)
Price (in/out)$0.6/$2.2 per 1M tokens $0.04/$0.15 per 1M tokens
Open weight?Yes — self-hostable No — API only
Modalitiestext, code text
SWE-Bench Verified73.8% Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Genuinely permissive open weights — an MIT-licensed 358B mixture-of-experts with no commercial restrictions

GLM 4.7

Open weights make this possible at all — Mercury 2.5 Preview is API-only, so it cannot leave the vendor's servers.

Strong agentic coding for the price — 73.8% on SWE-Bench Verified undercut most closed frontier models at launch

GLM 4.7

Mercury 2.5 Preview is comparatively weak here — 260K context window is far shorter than frontier 1M-token models

An unusually generous 128K maximum output, which suits bulk refactors and long generation

GLM 4.7

An MIT-licensed 358B open mixture-of-experts with strong 73.8% SWE-Bench Verified coding — but two generations behind GLM 5.2 — and its weights are open while Mercury 2.5 Preview is API-only.

Very high inference throughput (1,107 tok/s) via diffusion-based parallel token generation

Mercury 2.5 Preview

Its 260K tokens window holds about 1.3× more than GLM 4.7's 200K in a single prompt.

Coding accuracy (95.7%, 91st percentile among cost-optimized models)

Mercury 2.5 Preview

At $0.04/$0.15 per 1M tokens it undercuts GLM 4.7 ($0.6/$2.2 per 1M tokens), and that gap compounds at volume.

Mathematics accuracy (97.0%, 97th percentile)

Mercury 2.5 Preview

Inception Labs' August 31, 2026 diffusion-based language model preview, refining tokens in parallel for roughly 10x the throughput of comparable autoregressive models at cost-optimized-tier quality — and it runs cheaper at $0.04/$0.15 per 1M tokens.

Lowest cost at scale

Mercury 2.5 Preview

At $0.04/$0.15 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

Mercury 2.5 Preview

Its 260K tokens window is about 1.3× larger than GLM 4.7's 200K, fitting roughly 390 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

Mercury 2.5 Preview

At $0.04/$0.15 per 1M tokens it undercuts GLM 4.7, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Mercury 2.5 Preview

Larger 260K tokens window fits more in one prompt.

A team with data-privacy or self-hosting needs

GLM 4.7

Open weights let you run it on your own hardware; Mercury 2.5 Preview is API-only.

Anyone whose priority is genuinely permissive open weights — an mit-licensed 358b mixture-of-experts with no commercial restrictions

GLM 4.7

It is specifically built for that.

Anyone whose priority is very high inference throughput (1,107 tok/s) via diffusion-based parallel token generation

Mercury 2.5 Preview

That is its strongest area.

An enterprise with regional data-residency rules

Mercury 2.5 Preview or GLM 4.7

Origin (China vs US) affects where data is processed and which compliance regime applies — check the provider's terms for your region.

GLM 4.7: where it fits

An MIT-licensed 358B open mixture-of-experts with strong 73.8% SWE-Bench Verified coding — but two generations behind GLM 5.2. Released December 22, 2025 by Z.ai, it is built for genuinely permissive open weights — an MIT-licensed 358B mixture-of-experts with no commercial restrictions, strong agentic coding for the price — 73.8% on SWE-Bench Verified undercut most closed frontier models at launch, an unusually generous 128K maximum output, which suits bulk refactors and long generation, and cheap long-running agent loops thanks to aggressive prompt caching.

Its trade-offs are real: two generations behind — GLM 5, 5.1 and 5.2 have all shipped since, and new builds should default to those, its Verified lead narrows sharply on harder evaluations like SWE-Bench Pro, and text-only with no vision, and self-hosting a 358B model is a serious hardware commitment. At $0.6 in / $2.2 out per million tokens, it sits in the budget price band.

Mercury 2.5 Preview: where it fits

Inception Labs' August 31, 2026 diffusion-based language model preview, refining tokens in parallel for roughly 10x the throughput of comparable autoregressive models at cost-optimized-tier quality. Released August 31, 2026 by Inception Labs, it is built for very high inference throughput (1,107 tok/s) via diffusion-based parallel token generation, coding accuracy (95.7%, 91st percentile among cost-optimized models), mathematics accuracy (97.0%, 97th percentile), and tunable reasoning levels with parallel tool calls and schema-aligned JSON output.

Its trade-offs: 260K context window is far shorter than frontier 1M-token models, no vision or audio modalities, positioned only against cost-optimized models (GPT-5.6 Luna Low, Gemini 3.5 Flash-Lite), not frontier-class, and current $0.04/$0.15 pricing includes a limited-time launch promotion on OpenRouter (list price is $0.20/$0.75, may rise after Sept 8, 2026). At $0.04 in / $0.15 out per million tokens, it sits in the budget price band.

The bottom line for this matchup

The defining split here is open vs. closed. GLM 4.7 gives you weights you control — self-host it, fine-tune it, keep data in-house, pay only for hardware. Mercury 2.5 Preview gives you a managed, always-updated API with no infrastructure to run. Teams with GPUs, privacy requirements, or huge volume often favour the open model; teams that want zero ops and the latest capabilities favour the closed one. Capability is close enough that this operational question, not the benchmark, usually decides it.

Want both GLM 4.7 and Mercury 2.5 Preview without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is GLM 4.7 or Mercury 2.5 Preview better for coding?

Public SWE-Bench figures are not available for Mercury 2.5 Preview, so the honest test is your own repository — run an identical real bug through both. By design, GLM 4.7 leans toward genuinely permissive open weights — an mit-licensed 358b mixture-of-experts with no commercial restrictions while Mercury 2.5 Preview leans toward very high inference throughput (1,107 tok/s) via diffusion-based parallel token generation, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, GLM 4.7 or Mercury 2.5 Preview?

GLM 4.7 is open-weight, so self-hosting means no per-token fee (you pay for hardware instead), while Mercury 2.5 Preview is API-metered at $0.04/$0.15 per 1M tokens. For most teams without GPUs, the API model is cheaper to start; at very high volume, self-hosting can win.

Which has the bigger context window?

Mercury 2.5 Preview — 260K tokens vs 200K, about 1.3× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both GLM 4.7 and Mercury 2.5 Preview together?

Yes — a multi-model platform like LumiChats gives you GLM 4.7, Mercury 2.5 Preview and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, GLM 4.7 or Mercury 2.5 Preview?

Mercury 2.5 Preview — released August 31, 2026, about 8 months after GLM 4.7.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.