GLM 5.3 API Pricing
Z.ai (GLM) · context window 1.3M · prices updated 2026-09-29
Where GLM 5.3 sits on price
At $4.40 per million output tokens, GLM 5.3 is a mid tier model — 2.0× the median output price of $2.20, which puts it cheaper than 37% and pricier than 63% of the models we track. It sits 15th cheapest of the 18 Z.ai (GLM) models we track. Output costs 3.1× input, the usual spread — trim both, starting with the answer length.
Cached input is 81% cheaper. On an input-heavy workload you need roughly a 31% cache-hit rate to take 25% off the input line — reachable for chatbots and agents that resend the same system prompt and history.
What real workloads cost on GLM 5.3
These three workloads are the ones teams actually run on a mid-priced model — a $4.40/1M model is not bought for the same job as one ten times the price.
| Workload | Per request | Per month |
|---|---|---|
| Support chatbot — 500 conversations/day (5K in / 1.4K out) Conversation history re-sent each turn — the classic prompt-caching win. | $0.0132 | $197 |
| Document pipeline — 10K docs/day (3K in / 500 out) Batch-friendly: no user waiting, so a ~50% batch discount usually applies. | $0.0064 | $1920 |
| Long-context analysis — 200 runs/day (250K in / 4K out) Only possible on large-context models; input cost is nearly the whole bill. | $0.3676 | $2206 |
Model your exact traffic in the API cost calculator — it preloads GLM 5.3 with caching and batch options.
GLM 5.3 price history
Z.ai (GLM) last raised GLM 5.3's output price on Sep 27, 2026 (+269% per output token), from $0.3794/$1.19 to $1.40/$4.40 per 1M in/out. That is one of 9 repricings in the 39 days we have tracked it — worth knowing before you hard-code today's rate into a budget.
| Date | Input /1M | Output /1M | Output change |
|---|---|---|---|
| Aug 21, 2026 (tracking began) | $1.40 | $4.40 | — |
| Sep 13, 2026 | $1.09 | $3.43 | -22% |
| Sep 14, 2026 | $1.40 | $4.40 | +28% |
| Sep 19, 2026 | $0.91 | $2.86 | -35% |
| Sep 20, 2026 | $0.896 | $2.82 | -2% |
| Sep 21, 2026 | $0.91 | $2.86 | +2% |
| Sep 22, 2026 | $0.84 | $2.64 | -8% |
| Sep 25, 2026 | $1.40 | $4.40 | +67% |
| Sep 26, 2026 | $0.3794 | $1.19 | -73% |
| Sep 27, 2026 | $1.40 | $4.40 | +269% |
Change-points from our daily price snapshots (tracking since Aug 21, 2026; intraday moves between snapshots are not captured).
GLM 5.3 vs Qwen3.8 27B
The closest-priced alternative from another vendor is Qwen3.8 27B (Alibaba (Qwen)) — priced within a rounding error on output, with $1.36 less per million input tokens. When two models land this close on price, the decision is quality on your own workload, not the price sheet: run 50 real requests through both and compare.
See Qwen3.8 27B pricing →Cheaper alternatives
More Z.ai (GLM) models
Frequently asked questions
› How much does the GLM 5.3 API cost?
GLM 5.3 costs $1.40 per million input tokens and $4.40 per million output tokens, with cached input at $0.26 per million (81% cheaper). That works out to roughly 227,273 output tokens per dollar.
› What does the support chatbot workload cost on GLM 5.3?
Support chatbot — 500 conversations/day (5K in / 1.4K out) costs about $0.0132 per request and $197 per month on GLM 5.3. Conversation history re-sent each turn — the classic prompt-caching win.
› What does it cost to fill GLM 5.3's 1.3M context window?
Sending 1.3M of input in a single request costs $1.84 at $1.40 per million tokens — before any output. With prompt caching that same fill drops to about $0.3408 on repeat requests. This is why large context windows are cheap to advertise and expensive to actually use.
› Is GLM 5.3 worth the price?
GLM 5.3 sits in the middle of the market (15 of 18 by price within Z.ai (GLM)). The honest test is a routing experiment: send the same 200 real requests to this model and to a tier below, and compare failure rate against the price gap — most teams find a majority of traffic never needed the pricier model.