Variable Cost per Active License
What one actively used license costs per month: variable cost ÷ active licenses. Fixed costs are shown separately; teachers pay nothing (teacher-access cost stays on the Costs page); engineering tools and non-production are overhead.
How an active license is counted
An active license is a distinct student, with or without an account, on a licensed campus, who had actual usage in that month:
- 1
Usage that month only
Every graded result created in the calendar month (UTC) — scanned or online. Nothing carries over from earlier months.
- 2
Real activities only
An activity counts only if it received 10+ results that month; smaller ones (tests, dummies) are dropped.
- 3
Who the student is
Their account; otherwise the class-list entry (student number, else name); otherwise the name on the scanned sheet. Sheets with no name and no class-list entry are left out.
- 4
Licensed campus
The student's campus (or, without an account, the class teacher's) had a campus license live during the month. Pilot licenses count; DepEd partner universities (GradeChum in a Box) are excluded.
- 5
Each person once
Multi-page sheets, re-scans and students in several classes collapse to one. Class-list numbers and unique names on the campus merge into the matching account.
- 6
No dummies
Accounts on @codechum.com / @gradechum.com and test names (test, dummy, sample, demo, fake, qa, “Student 1”…) are excluded.
Name-only matches are the weakest identity — a misread name on a sheet can count one student twice.
$0.131
43,199 active licenses · 2026-10
▼ 24.6% vs 2026-09$5,648.33
2026-10 · 79% of user-serving
▲ 8.8% vs 2026-09$1,512.34
2026-10 · $0.035 / active license at this usage
▲ 4.3% vs 2026-09$1,228.28
Variable $339 · fixed $889 · on pace for ~$9,212
▲ 132.1% GCP vs same days last monthClick a month to open its line items below.
| Month | Active licenses | Variable | Fixed | Variable / license | All-in / license | Overhead | Total |
|---|---|---|---|---|---|---|---|
| 2026-11 month-to-date No note | 10,790 | $339.05 | $889.23 | $0.031 | $0.114 | $71.08 | $1,299.36 |
| 2026-10 No note | 43,199 | $5,648.33 | $1,512.34 | $0.131 | $0.166 | $499.69 | $7,660.36 |
| 2026-09 School year in full swing: active licenses jumped with the new term. Gemini 3.7 Flash is now the largest AI cost line. | 29,917 | $5,191.08 | $1,449.89 | $0.174 | $0.222 | $789.76 | $7,430.73 |
| 2026-08 Sem 1 starts; first month without the GCP promo credit. Variable cost is inflated by the processor idle-wait bug (~$1,355 on Aug 30–31 alone). | 11,254 | $3,968.43 | $1,365.53 | $0.353 | $0.474 | $809.85 | $6,143.81 |
| 2026-07 Last month covered by the GCP promotional credit (it ran out Aug 1–2); costs shown are before that credit. | 7,227 | $2,411.98 | $1,250.17 | $0.334 | $0.507 | $705.70 | $4,367.85 |
| 2026-06 Summer — low usage. GCP promo credit still covered the bill; costs shown are before that credit. No R2 usage split for this month (Cloudflare keeps ~13 weeks of analytics), so production R2 sits in the invoice remainder under overhead. | 6,845 | $1,221.44 | $1,206.14 | $0.178 | $0.355 | $633.61 | $3,061.19 |
| 2026-05 No note | 16,222 | $3,418.36 | $1,155.55 | $0.211 | $0.282 | $863.15 | $5,437.06 |
| 2026-04 No note | 18,043 | $3,227.26 | $1,181.87 | $0.179 | $0.244 | $2,843.20 | $7,252.33 |
| 2026-03AI estimated · no GCP infra No note | 17,182 | $3,064.01 | $991.80 | $0.178 | $0.236 | $415.08 | $4,470.89 |
| 2026-02AI estimated · no GCP infra No note | 13,587 | $1,597.94 | $867.48 | $0.118 | $0.181 | $726.93 | $3,192.35 |
| 2026-01AI estimated · no GCP infra No note | 1,841 | $514.28 | $814.08 | $0.279 | $0.722 | $779.39 | $2,107.75 |
| 2025-12AI estimated · no GCP infra No note | 8,306 | $944.44 | $836.34 | $0.114 | $0.214 | $78.50 | $1,859.28 |
| 2025-11AI estimated · no GCP infra No note | 9,047 | $1,525.88 | $825.07 | $0.169 | $0.260 | $33.47 | $2,384.42 |
| 2025-10AI estimated · no GCP infra No note | 10,075 | $641.09 | $830.85 | $0.064 | $0.146 | $72.28 | $1,544.22 |
Each student counts once, under the campus where most of their results are, so the counted rows add up to the month's active licenses. DepEd partner universities are shown but excluded; pilots are included. Est. variable cost = licenses × $0.174.
| University | Active licenses | Share | Est. variable cost |
|---|---|---|---|
| 17,887 | 59.8% | $3,103.68 | |
| PHINMA University of PangasinanMain Campus | 3,451 | 11.5% | $598.80 |
| University of St. LouisTuguegarao Campus | 2,158 | 7.2% | $374.45 |
| Mapua UniversityManila Campus | 1,509 | 5.0% | $261.84 |
| Our Lady of Fatima UniversityValenzuela Campus | 1,058 | 3.5% | $183.58 |
| University of San Jose-RecoletosMain Campus | 874 | 2.9% | $151.65 |
| Central Philippine UniversityMain Campus | 803 | 2.7% | $139.33 |
| St. Benedict Childhood Education CenterMain Campus | 526 | 1.8% | $91.27 |
| PHINMA Rizal College of LagunaMain Campus | 393 | 1.3% | $68.19 |
| University of CebuLapu-Lapu and Mandaue Campus | 321 | 1.1% | $55.70 |
| Free UniversityMain Campus | 275 | 0.9% | $47.72 |
| Mapua Malayan Colleges of MindanaoMain Campus | 261 | 0.9% | $45.29 |
| St. Dominic College of AsiaMain Campus | 260 | 0.9% | $45.11 |
| ChumLabs AcademyW/ License Campus | 128 | 0.4% | $22.21 |
| University of MindanaoMatina Campus | 10 | 0.0% | $1.74 |
| CodeChum AcademyMain Campus | 3 | 0.0% | $0.52 |
| Luray II National High SchoolDepEd · excludedMain Campus | 2,472 | excluded | — |
| Jacinto P. Elpa National High SchoolDepEd · excludedMain Campus | 206 | excluded | — |
| DEPED Free UniversityDepEd · excludedMain Campus | 74 | excluded | — |
| Total · 16 universitiesexcludes 2,752 DepEd | 29,917 | $5,191.08 |
Variable and all-in apply the month's platform-wide cost per active license to this university's active licenses. Measured AI is this university's own AI usage: Langfuse production cost by teacher → campus (or email domain) → university, scaled to the billed AI line; unmatched traces are spread pro rata. Use variable cost to project added cost for a new school; fixed costs don't grow with one more school.
| Month | Active licenses | Variable cost | Variable / license | All-in cost | Measured AI | Measured AI / license |
|---|---|---|---|---|---|---|
| 2026-11 month-to-date | 6,123 | $192.40 | $0.031 | $697.01 | $65.40 | $0.011 |
| 2026-10 | 20,108 | $2,629.15 | $0.131 | $3,333.10 | $1,940.23 | $0.096 |
| 2026-09 | 17,887 | $3,103.68 | $0.174 | $3,970.55 | $2,751.20 | $0.154 |
| 2026-08 | 8,326 | $2,935.95 | $0.353 | $3,946.20 | $588.46 | $0.071 |
| 2026-07 | 3,337 | $1,113.71 | $0.334 | $1,690.96 | $1,136.92 | $0.341 |
| 2026-06 | 4,227 | $754.28 | $0.178 | $1,499.11 | $360.54 | $0.085 |
| 2026-05 | 12,630 | $2,661.44 | $0.211 | $3,561.12 | $2,041.10 | $0.162 |
| 2026-04 | 11,676 | $2,088.43 | $0.179 | $2,853.24 | $2,545.09 | $0.218 |
| 2026-03AI estimated | 13,157 | $2,346.24 | $0.178 | $3,105.71 | $2,034.73 | $0.155 |
| 2026-02AI estimated | 10,898 | $1,281.69 | $0.118 | $1,977.49 | $1,165.11 | $0.107 |
| 2026-01AI estimated | 470 | $131.29 | $0.279 | $339.13 | $4.23 | $0.009 |
| 2025-12AI estimated | 7,160 | $814.13 | $0.114 | $1,535.08 | $584.10 | $0.082 |
| 2025-11AI estimated | 5,745 | $968.96 | $0.169 | $1,492.89 | $329.05 | $0.057 |
| 2025-10AI estimated | 7,077 | $450.32 | $0.064 | $1,033.94 | $485.70 | $0.069 |
| Average · 13 complete months | 9,438 | $0.173 | $0.247 / license | $0.130 |
Averages are per active license, weighted by licenses, over complete months (month to date left out). Months marked AI estimated predate the GCP billing export (Mar 2026): their GCP infrastructure isn't counted and Vertex AI is Langfuse traced cost × 1.26, so their all-in cost is understated.
School year in full swing: active licenses jumped with the new term. Gemini 3.7 Flash is now the largest AI cost line.
Vertex AI2 lines$4,362.40
- $4,114.17grading (production)Variable
Langfuse: 94.3% of traced AI cost is production
- $248.23evals, staging & localOverhead
Langfuse: 94.3% of traced AI cost is production
Cloud Run46 lines$1,068.19
- $661.15gradechum-api-productionVariable
- $228.31gradechum-overall-processorVariable
- $48.96gradechum-deped-queue-managerOverheadalways-on
- $26.28gradechum-answers-processorVariable
- $22.10questionnaire-to-gradechum-v3Variable
- $20.68gradechum-api-canaryVariable
- $16.41gradechum-api-stagingOverhead
- $8.05gradechum-sentry-discordOverheadalways-on
- $6.43questionnaire-pdf-generator-v2Variable
- $5.22gradechum-answersheet-downloadVariable
- $5.02gradechum-api-feature-aOverhead
- $3.86gradechum-analytics-gatewayOverhead
- $3.79gradechum-api-feature-cOverhead
- $3.67gradechum-overall-processor-stagingOverhead
- $2.74gradechum-api-feature-bOverhead
- $2.73gradechum-files-com-webhookFixedalways-on
- $1.78gradechum-mobile-file-uploadVariable
Neon2 lines$395.02
- $329.90Production DB, job queue & webhook stateFixed
Neon consumption history × Launch prices · fixed: mostly the always-on compute floor
- $65.12Internal dashboards, dev & other productsOverhead
Neon consumption history × Launch prices · fixed: mostly the always-on compute floor · 29 projects
Compute Engine16 lines$338.32
- $75.57gradechum-kiosks-managerFixed
- $67.09gradechum-kiosk-netbirdFixed
- $63.73gradechum-internal-analyticsOverhead
- $34.40gradechum-server-statuschecksOverhead
- $28.21Serverless VPC connectorsFixed
- $21.97extraction-qaOverhead
- $20.29vpn-proxyOverhead
- $7.88gradechum-kiosks-manager-ipFixed
- $7.16gradechum-e2e-static-ipOverhead
- $4.59gradechum-api-production-lb-feFixed
- $3.06snapshots of gradechum-internal*Overhead
- $2.45snapshots of gradechum-server-st*Overhead
- $1.52snapshots of gradechum-e2e-serve*Overhead
Sentry1 line$250.00
- $250.00Error monitoring planFixed
Flat $250/month (user, 2026-09-25) — monitors the production API, processor and mobile app
Langfuse1 line$228.61
- $228.61AI tracing planFixed
Invoice 2026-09-09: $228.61
Files.com1 line$199.00
- $199.00Scan intake planFixed
Assumed flat $199/month
Cloudflare4 lines$166.81
- $72.61R2 · gradechum-productionVariable
Measured R2 × list price: 4069 GB avg over 30 days
- $35.00gradechum.com plan & certificatesFixed
Current subscription list price
- $34.20R2 · staging & other bucketsOverhead
Measured R2 × list price: 2272 GB avg over 30 days
- $25.00Other zones (chumlabs.co)Overhead
Current subscription list price
Gemini API (API key)1 line$116.20
- $116.20Gemini API (API key)Overhead
Postmark1 line$60.00
- $60.00Transactional emailFixed
Assumed flat $60/month
Networking2 lines$55.91
- $52.04NAT, load balancer & ArmorFixed
- $3.87data transferVariable
Artifact Registry1 line$52.81
- $52.81Artifact RegistryFixed
Cloud Build1 line$52.35
- $52.35Cloud BuildOverhead
Cloud Memorystore for Redis1 line$41.20
- $41.20Cloud Memorystore for RedisFixed
Cloud Logging1 line$16.13
- $16.13Cloud LoggingVariable
Cloud Storage1 line$12.17
- $12.17Cloud StorageVariable
Secret Manager1 line$9.41
- $9.41Secret ManagerFixed
Cloud Monitoring1 line$2.45
- $2.45Cloud MonitoringFixed
Cloud DNS1 line$1.92
- $1.92Cloud DNSFixed
Cloud Scheduler1 line$1.25
- $1.25Cloud SchedulerFixed
BigQuery1 line$0.49
Cloud Pub/Sub1 line$0.09
For vendors without an automated feed. GCP (including AI) is synced automatically.