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DREXUS
ZRH · 07:26Request Proposal
§ T·06   Latency BudgetBUILD TBC-LAT-01RUNTIME LIVEv 1.4HomeToolsLatency Budget CalculatorFILED ·

Latency, itemized.
Excuses, retired.

Allocate a millisecond budget across frontend, backend, network, and database. Type a number, watch the math. The receipt prints itself.

Start the calculator
§ 01 — Inputs

Tell the truth.
The numbers will.

ms
95th-percentile time to interactive. Where the bar is.
req/day
For impact math. Be honest, not aspirational.
Current vs. Budget · ms
FrontendDOM, JS, paint900ms / 650ms
Content Download
cur
bud
+100ms
JS Parse & Execute
cur
bud
+100ms
Render & Paint
cur
bud
+50ms
BackendApp servers, business logic250ms / 200ms
Server Processing
cur
bud
+50ms
API Response
cur
bud
OK
NetworkDNS, TCP, TLS, RTT450ms / 390ms
DNS Lookup
cur
bud
OK
TCP Connection
cur
bud
OK
TLS Handshake
cur
bud
OK
Network RTT
cur
bud
+100ms
DatabaseQueries, indexes, locks150ms / 100ms
Database Query
cur
bud
+50ms
For analytics · optional
§ 02 — Receipt

Authentication Flow
performance.

Current P951750ms
Target P952250ms
StatusWithin budget
0msYou're shipping this. Don't break it.3150ms

Layer Breakdown

where the milliseconds go
Frontend51% of total
900msbudget 650ms
+250ms over
Backend14% of total
250msbudget 200ms
+50ms over
Network26% of total
450msbudget 390ms
+60ms over
Database9% of total
150msbudget 100ms
+50ms over

Component Ledger

line items, every ms accounted for
ComponentLayerCurrentBudgetΔStatus
DNS LookupNetwork20ms30ms−10OK
TCP ConnectionNetwork50ms60ms−10OK
TLS HandshakeNetwork80ms100ms−20OK
Server ProcessingBackend200ms150ms+50OVER
Database QueryDatabase150ms100ms+50OVER
API ResponseBackend50ms50ms0OK
Content DownloadFrontend300ms200ms+100OVER
JS Parse & ExecuteFrontend400ms300ms+100OVER
Render & PaintFrontend200ms150ms+50OVER
Network RTTNetwork300ms200ms+100OVER
Total1750ms1340ms+410OK

Action Items

  • Content Download is 50% over budget  · +100ms
  • JS Parse & Execute is 33% over budget  · +100ms
  • Network RTT is 50% over budget  · +100ms
  • Server Processing is 33% over budget  · +50ms
  • Database Query is 50% over budget  · +50ms
  • Render & Paint is 33% over budget  · +50ms
  • Frontend layer needs optimization  ·  900ms vs 650ms budget
  • Backend layer needs optimization  ·  250ms vs 200ms budget
  • Network layer needs optimization  ·  450ms vs 390ms budget
  • Database layer needs optimization  ·  150ms vs 100ms budget

Traffic Impact

if you ship it as-is
Daily traffic10,000req
Users over target500/5%
Bounce rate lift+0%
Conversion impactNegligible — within noise floor

Latency is a tax. Pay it, or pass it on. Most teams pass it on. Their users notice.

§ 03Method

How the numbers are calculated.

01

Pick a flow

Auth, checkout, search, feed — each has a different patience contract with the user. We default to P95 because it captures the long tail without chasing P99 ghosts.
02

Allocate by layer

Frontend, backend, network, database. Set a current and a budget per component. Every millisecond is accounted for or it doesn't exist.
03

Read the receipt

Headline status, layer headroom, line-item ledger, and traffic impact. The math is conservative — if it looks bad on paper, it's worse in production.
04

Pay the bill

One-click recommendation: pull every overshoot back to its budget. Then test it. Receipts don't lie, but they don't ship either.
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Get this audit, signed by a senior.

We use this exact model on every pod. If your latency budget is failing in production, book a 30-minute call and we'll walk you through your real numbers — not your aspirational ones.

FILED · · DREXUS® TOOLBOX · LBC
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