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 × $0.131.
| University | Active licenses | Share | Est. variable cost |
|---|---|---|---|
| 20,108 | 46.5% | $2,629.15 | |
| University of St. LouisTuguegarao Campus | 9,625 | 22.3% | $1,258.48 |
| University of MindanaoMatina Campus | 2,615 | 6.1% | $341.91 |
| Mapua UniversityManila Campus | 2,356 | 5.5% | $308.05 |
| Our Lady of Fatima UniversityValenzuela Campus | 2,005 | 4.6% | $262.16 |
| Central Philippine UniversityMain Campus | 1,813 | 4.2% | $237.05 |
| Mapua Malayan Colleges of MindanaoMain Campus | 1,324 | 3.1% | $173.11 |
| PHINMA University of PangasinanMain Campus | 938 | 2.2% | $122.64 |
| University of San Jose-RecoletosMain Campus | 842 | 1.9% | $110.09 |
| St. Benedict Childhood Education CenterMain Campus | 555 | 1.3% | $72.57 |
| University of CebuLapu-Lapu and Mandaue Campus | 323 | 0.7% | $42.23 |
| St. Dominic College of AsiaMain Campus | 299 | 0.7% | $39.09 |
| Free UniversityMain Campus | 282 | 0.7% | $36.87 |
| ChumLabs AcademyW/ License Campus | 114 | 0.3% | $14.91 |
| Luray II National High SchoolDepEd · excludedMain Campus | 2,163 | excluded | — |
| Jacinto P. Elpa National High SchoolDepEd · excludedMain Campus | 166 | excluded | — |
| DEPED Free UniversityDepEd · excludedMain Campus | 1 | excluded | — |
| Total · 14 universitiesexcludes 2,330 DepEd | 43,199 | $5,648.33 |
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.
Vertex AI2 lines$4,336.38
- $4,264.20grading (production)Variable
Langfuse: 98.3% of traced AI cost is production
- $72.18evals, staging & localOverhead
Langfuse: 98.3% of traced AI cost is production
Cloud Run79 lines$1,326.90
- $696.34gradechum-api-productionVariable
- $392.36gradechum-overall-processorVariable
- $50.78gradechum-deped-queue-managerOverheadalways-on
- $45.00gradechum-api-canaryVariable
- $31.59questionnaire-to-gradechum-v3Variable
- $26.27gradechum-api-loadtestVariable
- $15.94gradechum-api-stagingOverhead
- $14.22gradechum-answers-processorVariable
- $8.69questionnaire-pdf-generator-v2Variable
- $8.35gradechum-sentry-discordOverheadalways-on
- $7.97gradechum-answersheet-downloadVariable
- $7.84gradechum-api-codechum-23358-h-9526994598-previewOverhead
- $4.50gradechum-analytics-gatewayOverhead
- $3.74gradechum-overall-processor-stagingOverhead
- $2.83gradechum-files-com-webhookFixedalways-on
- $1.55gradechum-api-codechum-12279-f-3d0b8b0ad4-previewOverhead
- $1.45gradechum-api-codechum-12393-f-d3eb393c45-previewOverhead
- $1.40gradechum-api-feature-aOverhead
- $1.35gradechum-api-codechum-12325-f-f0189264d1-previewOverhead
- $1.22gradechum-api-codechum-12438-f-6b7072de86-previewOverhead
- $1.08gradechum-api-codechum-12281-f-df40dd0bb5-previewOverhead
Compute Engine20 lines$454.68
- $95.81gradechum-chum-memFixed
- $78.17gradechum-kiosks-managerFixed
- $69.58gradechum-kiosk-netbirdFixed
- $66.15gradechum-internal-analyticsOverhead
- $39.79gradechum-server-statuschecksOverhead
- $29.37Serverless VPC connectorsFixed
- $22.70extraction-qaOverhead
- $21.01vpn-proxyOverhead
- $8.21gradechum-kiosks-manager-ipFixed
- $7.46gradechum-e2e-static-ipOverhead
- $6.59gradechum-api-production-lb-feFixed
- $3.00snapshots of gradechum-internal*Overhead
- $1.67snapshots of gradechum-chum-mem*Fixed
- $1.60snapshots of gradechum-server-st*Overhead
- $1.57loadtest-runnerFixed
- $1.53snapshots of gradechum-e2e-serve*Overhead
Neon2 lines$328.78
- $304.68Production DB, job queue & webhook stateFixed
Neon consumption history × Launch prices · fixed: mostly the always-on compute floor
- $24.10Internal dashboards, dev & other productsOverhead
Neon consumption history × Launch prices · fixed: mostly the always-on compute floor · 25 projects
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
Estimate — no invoice recorded for 2026-10; using 2026-09
Cloudflare4 lines$201.27
- $106.15R2 · gradechum-productionVariable
Measured R2 × list price: 5112 GB avg over 31 days
- $35.12R2 · staging & other bucketsOverhead
Measured R2 × list price: 2284 GB avg over 31 days
- $35.00gradechum.com plan & certificatesFixed
Current subscription list price
- $25.00Other zones (chumlabs.co)Overhead
Current subscription list price
Files.com1 line$199.00
- $199.00Scan intake planFixed
Assumed flat $199/month
Artifact Registry1 line$67.05
- $67.05Artifact RegistryFixed
Networking2 lines$63.77
- $54.76NAT, load balancer & ArmorFixed
- $9.01data transferVariable
Postmark1 line$60.00
- $60.00Transactional emailFixed
Assumed flat $60/month
Cloud Build1 line$42.26
- $42.26Cloud BuildOverhead
Gemini API (API key)1 line$35.76
- $35.76Gemini API (API key)Overhead
Cloud Logging1 line$29.95
- $29.95Cloud LoggingVariable
Cloud Storage1 line$16.22
- $16.22Cloud StorageVariable
Secret Manager1 line$11.42
- $11.42Secret ManagerFixed
Cloud Monitoring1 line$3.85
- $3.85Cloud MonitoringFixed
Cloud DNS1 line$2.01
- $2.01Cloud DNSFixed
Cloud Scheduler1 line$1.81
- $1.81Cloud SchedulerFixed
BigQuery1 line$0.52
Cloud Pub/Sub1 line$0.12
For vendors without an automated feed. GCP (including AI) is synced automatically.