GLM-5.3-Flash Pricing: API Cost, Launch Discount & Real-World Usage
GLM-5.3-Flash API pricing as of August 30, 2026: $0.15 per million input tokens, $0.03 per million cached input tokens, $0.50 per million output tokens, with a 50% launch discount valid until September 9, 2026 24:00 (UTC+8). Zhipu prices the model at 1/10 of its GLM-5.3 flagship (1/20 during the discount) and about 1/40 of Claude Opus 4.8 — which makes it the cheapest 1M-context, coding-capable endpoint in the current open-model cohort. This page breaks down the official rates, what they mean at real usage levels, and how they compare with the models that shipped in the same week.
Pricing snapshot
Captured: August 30, 2026. Attribution note: Zhipu's official docs state only relative pricing (1/10 of GLM-5.3; 1/20 during the launch discount; ~1/40 of Claude Opus 4.8). The absolute USD figures below are as reported by third-party fact sheets (list tier) and as listed on OpenRouter, checked on 2026-08-30 (discount tier — OpenRouter currently serves the model at $0.075/$0.25/$0.015). The launch discount expires September 9, 2026 24:00 (UTC+8); list prices apply afterward. Re-verify in your billing console before budgeting — vendor pricing pages change without notice.
Official GLM-5.3-Flash API Pricing
| Token type | List price (per 1M tokens) | Launch price (50% off, until Sept 9, 2026 24:00 UTC+8) |
|---|---|---|
| Input | $0.15 | $0.075 |
| Cached input | $0.03 | $0.015 |
| Output | $0.50 | $0.25 |
| Cache storage | Temporarily free | |
Attribution: the launch-discount tier ($0.075 / $0.015 / $0.25) is confirmed by the OpenRouter listing (checked 2026-08-30); the list tier ($0.15 / $0.03 / $0.50) is as reported by third-party fact sheets reproducing Zhipu's published schedule. Zhipu's official docs state the relative framing only: GLM-5.3-Flash costs 1/10 of GLM-5.3 at list (1/20 during the launch discount) and about 1/40 of Claude Opus 4.8. For comparison, DeepSeek V4 Pro (pre-August 16 schedule) was $0.435 input / $0.87 output — GLM-5.3-Flash undercuts even that on input by ~3x at list. Note the flagship GLM-5.3 still has no published standalone API price as of this capture; it is available via the GLM Coding Plan's points system only (see our GLM-5.3 review).
Region & Channel Notes
- Currency. Zhipu's international docs publish USD prices (used above); the domestic bigmodel.cn platform bills in CNY. Always confirm the currency and locale in your own console — the two surfaces can differ in what they display.
- Model ID.
glm-5.3-flashon the Chat Completion API; also available inside the GLM Coding Plan for agent/IDE usage. - Platform resellers. Third-party gateways set their own prices and can differ from official rates. Checked on OpenRouter (2026-08-30): GLM-5.3-Flash is listed at $0.075/M input, $0.015/M cached, $0.25/M output (matching the launch discount tier), with a platform-declared context of 1,310,720 tokens / 131,072 completion tokens — platform-declared specs can differ from the official docs (1M context / 128K output). The same check on Qwen3.8 Flash shows $0.15/$0.47 per million (input/output) — different from Alibaba's official ¥0.8/¥2.7 — so never mix platform prices with vendor list prices. For multi-provider routing context, see our Modelflare review.
- Discount deadline. The 50% launch discount ends September 9, 2026 24:00 (UTC+8). If your workloads are price-sensitive, committing usage before that date effectively doubles your tokens per dollar.
GLM Coding Plan: Quota & Off-Peak Rates
For coding-agent usage, GLM-5.3-Flash is bundled into the GLM Coding Plan with a 3x quota compared to GLM-5.3, and calls outside peak hours consume 50% of standard points. Peak hours are weekdays 14:00–18:00 (UTC+8); weekends are entirely off-peak. Input, cached input, and output tokens are metered separately under the plan's points system, and ZCode adds a 1.5x limited-time quota boost through August 31, 2026. If you live in an IDE/agent workflow rather than raw API calls, the Coding Plan is usually the cheaper route than pay-per-token — the opposite of the recommendation for pure API services.
Real-World Cost Math
Monthly token volumes converted to dollars at GLM-5.3-Flash rates (list / launch-discounted):
| Usage profile | Monthly tokens (in / out) | Cost at list | Cost during 50% discount |
|---|---|---|---|
| Light API user | 10M in / 2M out | $2.50 | $1.25 |
| Typical dev tool | 50M in / 15M out | $15.00 | $7.50 |
| Heavy agent workload | 300M in / 100M out | $95.00 | $47.50 |
| High-cache RAG app (80% cache hits) | 300M in / 20M out, 240M cached | 240M × $0.03 + 60M × $0.15 + 20M × $0.50 = $24.70 | $12.35 |
Three practical takeaways. First, output tokens dominate — the 3.3x input/output price ratio means agentic workloads (which emit lots of code and tool calls) should be quoted on output volume, not input. Second, caching is the lever that matters: at $0.03/M, cached input is 5x cheaper than fresh input, so systems with stable system prompts (RAG, agents with persistent instructions) get an outsized benefit — and cache storage is temporarily free. Third, the launch discount effectively halves every row above until September 9.
GLM-5.3-Flash vs. Same-Week Competitors
The August 26–28 window produced three open-model price points to compare directly. Qwen3.8-Flash prices are published in CNY (¥0.8 input / ¥2.7 output / ¥0.1 cached per million); Hy4 preview at ¥6 / ¥18 with cache hits from ¥0.3. Approximate USD conversions (at ~7.1 CNY/USD, marked as estimates):
| Model (as of Aug 30, 2026) | Input / 1M | Output / 1M | Cached input / 1M | Context |
|---|---|---|---|---|
| GLM-5.3-Flash (list) | $0.15 | $0.50 | $0.03 | 1M |
| GLM-5.3-Flash (launch, until Sept 9) | $0.075 | $0.25 | $0.015 | 1M |
| Qwen3.8-Flash (API) | ¥0.8 (≈$0.11) | ¥2.7 (≈$0.38) | ¥0.1 (≈$0.014) | 1M |
| Tencent Hy4 preview (API) | ¥6 (≈$0.85) | ¥18 (≈$2.54) | from ¥0.3 (≈$0.04) | 1M+ |
| DeepSeek V4 Pro | $0.435 | $0.87 → $3.96 peak / $1.98 off-peak | $0.003625 | 1M |
| GPT-5.6 Luna (OpenAI budget tier) | $0.20 | $1.20 | — | — |
Read more in our GLM-5.3-Flash vs Qwen3.8-Flash-Next and price & speed comparison, plus the Hy4 preview review and DeepSeek V4 Pro review for their pricing details.
Who Is GLM-5.3-Flash Pricing For?
- Indie developers & startups — a full month of heavy agent use (~50M in / 15M out) costs $7.50 during the discount; that's the cheapest capable 1M-context agent endpoint available this week
- High-volume RAG / document pipelines — 1M context plus a $0.03 cache rate makes whole-repository or whole-manual processing viable without chunking
- Prototyping teams — lock in the discount before September 9 if you expect sustained usage
- Self-hosting teams — if per-token pricing still feels expensive, MIT weights + SGLang/vLLM remove the meter entirely (see the full GLM-5.3-Flash review)
Things to Watch
- The launch discount ends September 9, 2026 24:00 (UTC+8) — list prices are 2x the discounted rates.
- GLM-5.3's standalone API price is still unpublished; if it lands below expectations, the "1/10 of flagship" framing may shift.
- CNY vs USD billing differences across bigmodel.cn and international surfaces can change effective costs by a few percent depending on the exchange rate.
- DeepSeek's peak/off-peak schedule and Hy4's free-trial windows (2 weeks on WorkBuddy/CodeBuddy) are the two most likely pricing moves to change the competitive picture in September.
Bottom Line
At $0.15 / $0.50 per million tokens — half that until September 9 — GLM-5.3-Flash is the value anchor of the August open-model cohort: the cheapest 1M-context coding-capable API, with a 5x-cheaper cache tier and free cache storage on top. The price is only half the story, though: its review page documents where the efficiency trade-offs show up (reasoning, some vision suites). Our independent take: for budget-constrained agent and RAG builders, this is the default starting point this week — but budget on list prices, not the discount, for anything past mid-September.
FAQ
What is GLM-5.3-Flash API pricing?
$0.15 / $0.03 / $0.50 per million tokens (input / cached input / output) at list, captured August 30, 2026; cache storage temporarily free.
How long does the launch discount last?
The 50% discount ($0.075 / $0.015 / $0.25) is valid until September 9, 2026 24:00 (UTC+8).
Is GLM-5.3-Flash cheaper than GLM-5.3?
Yes — 1/10 of GLM-5.3's price per Zhipu (1/20 during the discount). GLM-5.3's standalone API price was unpublished as of August 30, 2026.
Does the GLM Coding Plan include GLM-5.3-Flash?
Yes — fully available with 3x the quota of GLM-5.3, and 50% point consumption outside peak hours (weekdays 14:00–18:00 UTC+8, plus weekends).
How much does GLM-5.3-Flash cost at scale?
50M in / 15M out per month ≈ $15 at list ($7.50 discounted). Heavy agent use (300M in / 100M out) ≈ $95 at list ($47.50 discounted). Cache-heavy RAG cuts input cost 5x.
Sources (accessed August 30, 2026): Zhipu official docs (docs.bigmodel.cn — GLM-5.3-Flash relative pricing), z.ai/subscribe (GLM Coding Plan), OpenRouter listing for z-ai/glm-5.3-flash (discount-tier prices, checked 2026-08-30), third-party fact sheets reproducing Zhipu's published price schedule (list tier, discount deadline), DeepSeek V4 Pro official pricing as documented in our DeepSeek V4 Pro review, Qwen3.8-Flash pricing from Alibaba's official platform and OpenRouter listing, Hy4 pricing from Tencent's official announcement. USD conversions for CNY prices are estimates at ~7.1 CNY/USD. ToolStep claims no laboratory test results; prices re-verify in vendor consoles.