Test. Mock. Automate.Without leavingyour laptop.VPC.machine.company.terms.

callman is the local-first API workspace for teams who can't ship through a third-party cloud. HTTP requests, no-code scenarios, contract tests, mock APIs, and a CLI runner — six products, one desktop app, zero data leaving your machine.

See it in actionDownload
No-code Scenario BuilderCollection RunnerCreate ScheduleContract RuleDatabase tab inline in requestBuilt-in dev tools
6products, one app
0data sent to vendor cloud
DB · Kafka · Redisinline, per request
HTTP requests⟢No-code scenarios⟢Mock APIs⟢Contract tests⟢Inline Database⟢Inline Kafka⟢Inline Redis⟢JWT decoder⟢Diff checker⟢Base64 · UUID · files⟢callme CLI⟢Slack reports⟢Schedules⟢HTTP requests⟢No-code scenarios⟢Mock APIs⟢Contract tests⟢Inline Database⟢Inline Kafka⟢Inline Redis⟢JWT decoder⟢Diff checker⟢Base64 · UUID · files⟢callme CLI⟢Slack reports⟢Schedules⟢
Local-first, by design

Your APIs.Your data.Your laptop.

Other tools want your tokens, your collections, and your traffic. Callman runs as a desktop app. Your secrets stay in your keychain. Your data stays inside your network. The cloud is opt-in — never the default.

On-prem by default

Open the .dmg, log in to your team, start sending requests. Nothing leaves your machine without an explicit toggle.

Bring your own infra

Database, Kafka and Redis connections live in your workspace. Callman speaks to them directly — no proxy, no relay, no middleman.

Self-hosted control plane

Admin panel, RBAC, audit log, backup/restore — deploy the whole stack in your VPC. Or skip it entirely.

01 / Product

Six products.
One workspace.

Each tool is a thin, opinionated surface on top of the same engine. Move between requests, scenarios, mocks and the CLI without ever leaving the app.

Requests POSTGET

A first-class HTTP request manager. Collections, environments, authorization, scripts, contract rules — the basics, done right.

→
Scenarios no-code

Drag-and-drop test flows for QA. Wire up requests, conditions, scripts, DB queries and Kafka events on a canvas. Validate, then schedule.

→
Mock APIs for BAs

Spin up fake endpoints from a real response — or write them by hand. Frontends unblock themselves while backends finish shipping.

→
Contracts schema

Hover any JSON field, add a rule. Required, type, length, regex, enum. Saved rules run on every response — locally and in CI.

→
callme CLI

Collection runner with scheduling and Slack delivery. callme run --collection-id=… --env-id=… in your GitHub or GitLab pipeline.

→
Dev Tools offline

JWT decoder, Base64, UUID converter, diff checker, file converter. The utilities you'd otherwise paste your tokens into a random website for.

→
03 / Who it's for

One workspace.
Four roles.

BACKEND

Send the request.
Seed the row.
Assert the event.

  • HTTP requests with full auth + scripting
  • Inline Database, Kafka, Redis
  • Contract testing per endpoint
  • Per-environment connections
QA

Build the flow.
Schedule smoke & regression.
Sleep through the night.

  • Drag-and-drop Scenario Builder
  • Conditions, scripts, waits, aggregators
  • Daily schedules with Slack reports
  • Retry & max-runtime policies
BUSINESS ANALYSTS

Mock the API.
Hand it to the frontend.
Move on.

  • Mock endpoints from real responses
  • No backend round-trip needed
  • Version-controlled in the workspace
  • Live preview & shareable links
FRONTEND

Hit the mock.
Decode the token.
Diff the JSON.

  • Local mock APIs in one click
  • JWT decoder, Base64, file convert
  • Side-by-side JSON diff checker
  • UUID conversion utilities
04 / Take the tour

Five ways Callman changes how you work.

A closer look at the parts that matter. Every screen below is real product, redrawn — drag, drop, connect, schedule, assert, ship.

01Scenarios

A flowchart that actually runs.

Drag a Request onto the canvas. Connect it to a Database query. Pipe the result into a Script, gate it with a Condition, wait, then assert the Kafka event arrived. Every node has a label, an output, and a strict-fail switch.

  • ✓ 11 node types: Request, Condition, Wait, Script, Database, Kafka, Redis, Notification, Aggregator, Sub-scenario, End
  • ✓ Labelled outputs feed any downstream node via {{Label.field}}
  • ✓ Strict-fail stops the run · soft-fail keeps it going and reports
  • ✓ Execution log tells you exactly which node fell over, and why
No-code Scenario Builder — node palette and canvas.
Scenario Builder · failed run, strict-fail nodes, execution log
02Schedules

Any time, any day. Slack alerts you on failure.

Schedules turn scenarios into background jobs. Pick a timezone, set the times, decide what happens when one run overruns the next. Failure notifications go straight to Slack — with the exact failing node attached.

  • ✓ Timezone-aware: UTC, Europe/London, anything in your TZDB
  • ✓ Daily, weekly or cron-string triggers · multiple run-times per day
  • ✓ Skip overlapping runs or allow them parallel
  • ✓ Max-runtime safety cap · retry-on-fail policy
  • ✓ Slack on failure, ping on success, or stay quiet
Create Schedule modal — timezone, daily trigger, execution policy.
Schedule · timezone-aware, overlap-safe, slack on failure
03Reports

Every run, fully logged.

After each scheduled run the full report is one click away. Execution path, per-node timeline, duration, retries — and exactly which node failed, so you can fix it without re-running the whole scenario.

  • ✓ Execution path — success, failed, skipped colour-coded per node
  • ✓ Per-node timeline: attempts, duration, contract results
  • ✓ Jump to map highlights the exact failing node on the canvas
  • ✓ Export the report or re-run failed nodes only
Schedule run report — execution path, node timeline, failed nodes.
Schedule Report · execution path, node timeline, re-run failed
03Contracts

Hover a field. Add a rule. Done.

Contract rules ride along with every request. Hover any JSON field, click the ＋, and pick from required, type, length, regex, enum. Saved rules run on every response — locally, in CI, and on schedule.

  • ✓ Eight rule kinds: required, not-empty, type, min/max length, contains, pattern, enum
  • ✓ Per-field, not per-response — pin exactly what matters
  • ✓ Disabled rules stay visible but don't participate in validation
  • ✓ The same rules run under callme run in CI
Add Contract Rule panel — required, not-empty, type, length, pattern.
Contract Rule · per-field validation that ships with the request
04Runner

Run the whole collection. See what fell over.

Click Run on any collection. The runner fires every request in order, honours your environment variables, and shows you a per-request table with status, code, latency, and the time it executed. Re-run the failures only. Export the report.

  • ✓ Configurable delay between requests · per-request timeout
  • ✓ Variables flow from one request to the next (token → next call)
  • ✓ Re-run failed only · or rerun a single row
  • ✓ Same runner powers the callme CLI in your pipeline
Collections view — organised requests ready to run.
Collection Runner · per-row latency, retry failed, export report
05Import

Your other-app collections. Home in a second.

Bring your existing collections from Postman, Insomnia, or any OpenAPI-compatible tool in one click. Collections, environments, and scripts land exactly where you'd expect them — nothing to rebuild.

  • ✓ Import from Postman, Insomnia, or any OpenAPI spec
  • ✓ Collections, environments and scripts preserved intact
  • ✓ Done in under a second — no rebuilding by hand
  • ✓ Start running requests immediately
Collection import — importing from another API client in one click.
Collection Import — from any API client, instantly
05 / CLI

Ship it through
callme.

Same engine, headless. Plug it into GitHub Actions or GitLab CI with one flag. Backwards-compatible with the runner you already wired up.

~/repo · GitHub Actions runner
$ callme run \
    --collection-id=cm_col_a4f… \
    --env-id=cm_env_test \
    --token=$CM_PAT \
    --reporter=slack

→ Fetching collection from workspace…
→ Resolving 12 environment variables…
→ Running 8 requests · 7 contract rules · 1 scenario

  ✓ POST  1 - register by Pin            200  4.60 s
  ✓ POST  4 - Login - by userId + passcode 200  187 ms
  ✓ POST  5 - Token                       200  1.31 s
  ✓ GET   6 - Get User Info               200  118 ms
  ✓ GET   7 - User                        200  117 ms
  ✓ POST  Refresh Token                   200  187 ms
  ✓ POST  2 - verify otp                   200  1.29 s
  ✓ POST  3 - set passcode                 200  340 ms

PASS  8/8 requests · 0 failed · total 10.19s
→ Posted summary to #qa-smoke (Slack)
06 / Tools

The utilities you used to paste
your tokens into.

JWT decode, Base64 encode, UUID convert, JSON diff, file converter — all bundled, all offline. Stop sending company tokens to random websites.

01
10

Base64

Encode and decode UTF-8 or files. Live debounce, 300 ms.

⌬

UUID Tool

Convert dashed UUIDs to compact hex and back.

⇄

Diff Checker

Side-by-side JSON / text with structural highlights.

⚿

JWT Decoder

Header, payload, expiry — never leaves your machine.

HEADERPAYLOADSIG
eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxMjM0NSI….9KuTgZ…
sub12345
issiam-svc
exp2026-06-01
⛯

File Converter

Files ↔ Base64 with preview and export.

08 / Pricing

Pick an API Request Client plan.

Every tier includes all six Callman products and the local-first desktop app. Upgrade for AI credits, collaboration, scenario runners, governance and on-prem deployment.

API Request Client

HTTP · Mocks · Collections · Dev Tools
Who is this for?

Backend Engineers

Fire HTTP requests, inspect responses, and debug live APIs without leaving the desktop.

Frontend Developers

Consume mock APIs on day one — no waiting on backend. Run collections against staging before every deploy.

DevOps & Platform

Plug the CLI runner into CI/CD pipelines. Schedule smoke tests, get Slack alerts on failure.

API Architects

Design-first with mock servers and OpenAPI specs. Share collections and contracts across teams.

Security Engineers

Everything stays on-prem. No tokens sent to a third-party cloud. SOC 2-aligned by default.

Business Analysts

Explore live APIs and build mock flows without writing code. Share results with stakeholders instantly.

Free

For individuals exploring and building APIs.

$0per month
Desktop app · forever free
Download free
  • 50 AI credits
  • API client & core tools
  • Mock servers & specs
  • Native Git sync
  • Collection Runner
  • Performance testing
  • Contract testing — rules per field

Solo

For individuals who want to move faster with AI.

$6per month
billed annually
Start free trial

1 month free trial

Everything in Free, and:

  • 400 AI credits / month
  • Data-driven testing with exports
  • Custom-branded documentation
  • Unlimited custom domains
  • Expanded API monitoring
  • Unlimited private NPM packages
  • Unlimited inline DB / Kafka / Redis
Most teams pick this

Team

For teams building and shipping APIs together.

$14per user / month
billed annually
Start free trial

1 month free trial

Everything in Solo, and:

  • 400 AI credits / user / month
  • Team collaboration & workspaces
  • SDK generation
  • Basic RBAC
  • Shared collections & mocks
  • Simple Security
  • Shared scenarios & contract rules
  • Parallel collection runners (4×)
  • 90-day run history & dashboards

Enterprise

For organizations distributing APIs at scale.

$39per user / month
billed annually · committed seats
Talk to sales

1 month free trial

Everything in Team, and:

  • 800 AI credits / user / month (pooled)
  • API Catalog & Private Network
  • Unlimited private & partner workspaces
  • Advanced RBAC & org controls
  • Governance, audit logs & reporting
  • Advanced Security
  • Insights & analytics
  • SSO & SCIM provisioning
  • Self-hosted on-prem deployment
  • Private VPC runners
  • Named CSM · 24h SLA

Pick a QA Automated Platform plan.

QA Automated Platform

Scenarios · Contracts · Schedules · CI
Who is this for?

QA Engineers

Build no-code test scenarios in minutes. Run contract assertions on every response automatically.

Test Leads

Manage parallel scenario runners, 90-day history, and trend dashboards across the whole team.

Backend Engineers

Wire Kafka events, Redis commands, and DB queries directly into test flows — no extra tooling.

CI/CD Engineers

Schedule daily smoke & regression with callme CLI. Get Slack alerts, full execution logs in CI.

Engineering Managers

Track test coverage, run history, and failure trends. Governance and audit logs for compliance.

Compliance & Security

Self-hosted on-prem option. No test data leaves the network. Advanced RBAC and SSO ready.

No-code scenario builder — wire requests, Kafka events, Redis commands and DB queries on a visual canvas. Contract rules per field — required, type, regex, enum. Run automatically on every response, locally and in CI. Scheduled smoke & regression — daily runs, Slack on failure, full execution log. Everything Postman's test layer was missing.

Free

For individuals automating their first API tests.

$0per month
Desktop app · forever free
Download free
  • 50 AI credits
  • Collection Runner & Performance Testing
  • Manual Flows
  • Contract testing — rules per field
  • Basic scenario builder
  • Native Git for test versioning
  • Contract testing — rules per field

Solo

For solo engineers running tests in CI.

$7per month
billed annually
Start free trial

1 month free trial

Everything in Free, and:

  • 400 AI credits / month
  • Unlimited no-code scenarios
  • callme CLI for CI · 5 schedules
  • Inline DB / Kafka / Redis
  • Data-driven testing with exports
  • Unlimited contract rules
  • Unlimited inline DB / Kafka / Redis
  • Unlimited no-code scenarios & contracts
  • callme CLI for CI · 5 saved schedules
Most teams pick this

Team

For QA teams running automated test suites.

$29per user / month
billed annually
Start free trial

1 month free trial

Everything in Solo, and:

  • 400 AI credits / user / month
  • Parallel scenario runners (4 concurrent)
  • Shared scenarios & contract rules
  • 90-day run history & trends
  • Team test collaboration
  • Advanced RBAC for test access
  • Parallel scenario runners (4 concurrent)
  • Shared scenarios & contract rules
  • 90-day run history & trend dashboards

Enterprise

For enterprises with compliance and scale needs.

$68per user / month
billed annually · committed seats
Talk to sales

1 month free trial

Everything in Team, and:

  • 800 AI credits / user / month (pooled)
  • Private test & Flows runners
  • Governance & audit logs
  • Insights & test analytics
  • Self-hosted test infrastructure
  • Advanced security & compliance
  • Unlimited parallel scenario runners
  • Custom test data retention
  • Private VPC scenario runners
  • Self-hosted on-prem deployment
  • SSO & SCIM provisioning
  • Private VPC scenario runners
  • Named CSM · 24h SLA
Callman-only feature — not in Postman

Stop sending
your data
to strangers.

Callman is a free download for individuals. Team plans start at $14/seat/month. Self-host the control plane if you want to.

macOSApple SiliconM1–M4 · .dmgDownloadmacOSIntelx86_64 · .dmgDownloadWindows10 / 11 · ARM64ARM64 · .exe installer · Windows 11 (ARM)DownloadWindows10 / 11x64 · .exe installerDownload

Open the installer → sign in → start sending requests. No credit card. No tracking pixel. No phone-home.

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